Options and Obstacles Living with Low Water Flows in the Mattole River Headwaters

Sanctuary Forest, November 2004 Prepared by Tasha McKee

Mattole River at Lowest Acceptable Summer Flows, 0.2 cfs, August 24, 2004

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Large Capaci

ry Reach of Mattole River, September 28, 2004

ty Water Storage Tanks Can Help Keep the Mattole Flowing

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TABLE OF CONTENTS

Acknowledgements

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Introduction

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Water Shortages and Solutions – A Global Context

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Mattole River History – Climate, Culture and Fisheries

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Mattole Headwaters Low Flows – Historical Context and Current Conditions

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Possible Causes of the Low Flow Problem • Climate Changes • Land Use History • Population and Water Use Increases

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Possible Solutions to the Low Flow Problem – Voluntary Measures • Water Conservation and Management Practices

1. Water Storage – Tanks and Ponds 2. Water Conservation and Efficiency 3. Water Rights in the Mattole 4. California Water Rights 5. Landowner Agreements for Streamflow Protection 6. Monitoring of Landowner Agreements 7. Permitting and Compliance Issues

○ Water Storage Permits ○ Taxation of Storage Tanks and Ponds

• Water Enhancement to Supplement Flows • Funding for Voluntary Measures

1. Funding Available Directly to Landowners 2. Funding Through Non-profit Programs for Private and Public Lands 3. Funding Through a Resource Conservation District (RCD) 4. Funding From Foundations and Private Sources

1414151617181923242424252626272728

Compulsory and Regulatory Measures • Fully Appropriated River • Adjudicated Water Rights • County General Plan Amendment • California Department of Fish and Game Regulations for Fish and Wildlife • Assessment of Compulsory and Regulatory Measures • Agency and Community Cooperation

28282930303131

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Proposed Projects to Improve Mattole Streamflows • Hydrology Assessment • Education and Community Outreach • Water Conservation and Storage

1. Funded Water Storage 2. Landowner Agreements for Streamflow Protection

• Water Enhancement Projects to Supplement Flows 1. Recharge Ponds 2. Brush Clearing and Forest Thinning 3. Groundwater Pumping

32323334343535353637

Ongoing Projects to Improve Mattole Streamflows • Water Conservation and Storage

1. MRC Education, Outreach, and Water Conservation Tune-ups 2. Pioneer Tank Installations 3. Pilot Project- Water Conservation Easement

• Water Enhancement Projects to Supplement Flows 1. Sediment Removal 2. Fish Habitat Structures

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References and Literature Cited 41List of Figures

1. Figure 11: Low flows at five sites in the Upper Mattole River, 2004 2. Figure 12: Late summer flow recession in the Upper Mattole River, 2004

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Appendices Appendix A: Sanctuary Forest River Monitoring and Project Maps

1. Site Map for River Flow Measurements 2. Site Map for Proposed Projects

Appendix B: Department of Fish and Game Map, “Mattole River Water Diversions” Appendix C: “Preliminary Hydrologic Assessment of Low Flows in the Mattole

River Basin,” Randy Klein, September 2004

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ACKNOWLEDGEMENTS

Sanctuary Forest would like to extend the deepest thanks to our funders, partners, consultants and community volunteers, who have played an invaluable role with the research and river flow monitoring contained in this report. We would also like to thank the many agencies and individuals who shared their knowledge. Using the knowledge contained in this report, the Mattole community, friends, and partners can begin taking effective steps toward solving Mattole River low flows. Funders

• The California Coastal Conservancy • The Bureau of Land Management

Partners

• Mattole Salmon Group • Mattole Restoration Council

Consultants

• Randy Klein, Hydrologist • Robert Donlan, Water Law Attorney

River Monitoring

• Volunteers Rebecca McKee, Sita Formosa, Lela McKee Friel, Kathy Orcutt, A. J. Machi, C. Moss, Whitethorn School

• Agencies California Department of Fish and Game

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INTRODUCTION Water shortage has become a global problem necessitating a change in how we perceive and use water. When resources are abundant we tend to use more than we need. Today’s water scarcity challenges us to recognize the preciousness of water and learn how to steward this resource for the benefit of people and all other living things. The community of the Upper Mattole is experiencing water shortages locally. Starting in 1997, the Mattole Headwaters have been impacted by extreme low flows in the late summer and early fall months. This report begins with an overview of water shortage problems within a world context. The report then describes our local low flow problems within a historical context, discusses possible causes and solutions, and summarizes proposed and ongoing projects. WATER SHORTAGES AND SOLUTIONS – A GLOBAL CONTEXT The following discussion of water availability was summarized from an extensive, well- researched article published by National Geographic in September 2002.1 Freshwater constitutes only about 2.5% of the total volume of Earth’s water. Most of this freshwater is not accessible. Approximately 69% of the world’s freshwater is frozen in glaciers, permanent snow cover, ice and permafrost. Thirty percent of all freshwater is underground with most of it in deep, hard-to-reach aquifers. The remaining 1% is divided between lakes and rivers, soils, wetlands, and biota, and atmospheric water vapor. Only a fraction of 1% of Earth’s water is available for drinking, irrigation, and industrial use. We can desalinate seawater but not economically. Only 10% of the water used worldwide is for household use. Agriculture takes 70% and at least half of that is lost to evaporation or runoff. Industry consumes the remaining 20%. Water waste is significant. Drip irrigation uses 30% to 70% less than traditional methods and is currently used on less than 1% of irrigated land. Industrial water use could be reduced by more than half through conservation measures and water reuse. A shortage of freshwater is at the top of the list of environmental problems confronting humanity in the 21st century. The United Nations has predicted that 2.7 billion people (35% of the estimated population) will face severe water storages by 2025 if consumption continues at current rates. Today an estimated 1.8 billion people are classified as highly water-stressed populations with basic water needs not being met. All over the world freshwater is being used faster than it can be replenished. Current water use poses a serious threat to rivers, wetlands, and lakes. China’s Yellow River, utilized extensively by farmers and cities has failed to reach the sea most of the past 10 years. In Central Asia the Aral Sea shrank by half after the Soviets began diverting water for cotton and other crops. In North America the Colorado River barely makes it to the Gulf of California and the Rio Grande dried up before it merged with the Gulf of Mexico in 2001. California’s Tule Lake is one tenth the size it was a century ago with most of the water going to diversions for agriculture. Elsewhere, countless small rivers have gone dry. In a trend

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echoed worldwide, 90% of California’s wetlands have disappeared, and 39 of 67 native fish species are extinct or at risk of extinction. Also worldwide, there is a growing awareness of the preciousness of water and the need to get more out of every drop. Fen Montaigne of National Geographic described his 2-month trip to Africa, India and Spain where he discovered a host of individuals, organizations and businesses working to solve water shortages. The solutions range from revival of ancient techniques to 21st century technology. They all have two things in common: a desire to maximize efficient use of every drop of water, and a belief in using local solutions and free-market incentives in their conservation campaigns. The solutions include rainwater harvesting, treadle pumps for low impact water withdrawals, conversion to drip irrigation, and computerized control of irrigation based on sensor probes and seasonal requirements. Metropolitan water conservation includes system repairs to eliminate leaks, replacement of residential fixtures with water-efficient toilets, showerheads and water taps, and treatment of wastewater for reuse. Scientist Stuart Pimm discusses world water use in his book The World According Pimm.2 He quotes scientist Peter Gleick’s calculations for basic human water requirement: 50 liters per day for personal use only. The average Californian uses over 10 times this amount. The Netherlands and Sweden use 100-200 liters per day. About 1 billion people live in countries where average water use is less than the 50 liter amount. According to a report on the state of California rivers published by the Trust for Public Land, seven out of 17 north coast rivers, including the Mattole, are impacted by low instream flows.3 Research and implementation of water conservation measures to enhance instream flows has become the forefront issue for individuals, groups and communities committed to healthy rivers and survival of threatened salmonids. On the Scott River in Northeastern California, low instream flows have severely impacted agriculture and residential use as well as the fisheries. A water trust for the Scott River is being considered to facilitate conservation measures that will benefit people as well as fish.4 MATTOLE RIVER HISTORY – CLIMATE, CULTURE AND FISHERIES The Mattole River is located in northern Mendocino and southern Humboldt Counties on the Northern California coast. The river drains a 296-square-mile watershed, and flows 62 miles northwest from its headwaters, located 5 miles south of Whitethorn, to its mouth near Petrolia. The climate is characterized by dry warm summers and wet winters. The Mattole River Basin has one of the highest annual rainfalls in California with a mean rainfall of about 81 inches and most of the precipitation occurring during the months of November through April.5 The rugged topography and climate of the Mattole has played a big role in making the basin as remote and sparsely populated as it is today. The main coastal highways of California circumvent the Mattole and the one-and two-lane roads in the basin are not well maintained. It has been historically difficult to make a living here and the heavy winter rainfalls drive away many potential settlers.

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Early settlers in the Mattole worked hard to make a living. Much of the river basin has steep, mountainous terrain, making farming difficult. Many homesteaders put together a living through a combination of logging, farming, and raising sheep, and also relied on the abundant sources of fish and wildlife to feed their families. During the 1950s and 1960s tractor logging brought a timber boom to the Mattole. Timber harvesting occurred at an accelerated rate along with the construction of thousands of miles of skid logging roads.6 Small mills proliferated during this time, only to shut down by the early 1970s as the harvestable timber was exhausted. New homesteaders, looking for a healthier way of life away from the cities, came to the Mattole in the 1970s. Many of the new settlers came with a dream of creating a healthy life for themselves and the land. The challenges of making a living here were still difficult. There were very few jobs available, and many people started cottage industries or combined seasonal work such as firewood and substitute teaching to support themselves. Marijuana growing became a way to supplement income and by the 1980s it had become part of the local economy and culture. Increased tourism in the 80s and 90s also contributed to the local economy. Along with the improved economy came a higher standard of living and increased consumption. Historically, the Mattole River was one of the better Chinook, coho and steelhead trout producers of the entire California coast, with pre-1950 populations estimated at eight to ten thousand for each species.7 Over the past four decades Mattole salmon runs have declined sharply, with both Chinook and coho dropping from about 3,000 in 1981-82 to around 100 in the 1990-91 season.8 In response to this sharp decline, all three species have been federally listed under the Endangered Species Act as “threatened”; also, as marine resources, these species are under National Oceanographic and Atmospheric Administration (NOAA) stewardship. The coho of the Southern Oregon/Northern California Coasts were federally listed in 1997. The California coho were listed as threatened under the state Endangered Species Act in 2002. In the early 1980s the Mattole communities became very concerned about the declining salmon runs. Concerned and committed local residents volunteered numerous hours to develop a native hatchery program and participate in hand restoration projects. The task of recovery was huge, and non-profits were formed to work with federal and state agencies in order to bring in the resources needed to save the Mattole salmon from extinction. The Mattole Salmon Group (MSG), the Mattole Restoration Council (MRC), Sanctuary Forest, Inc. (SFI), and the Coastal Headwaters Association are non-profit organizations that formed to assist in habitat recovery and protection. The Upper Mattole River and Forest Cooperative (UMRFC) was formed to collectively manage 4000 acres of land conserved in the Mattole Headwaters. Over the past 20 years these organizations have developed, funded and implemented numerous fishery recovery projects. The Mattole Salmon Group developed a native hatchbox and rescue-rearing program and fish habitat enhancement structures. MSG also accomplished monitoring of fish populations and stream channel sedimentation trends. The Mattole Restoration Council was the first organization to do sediment source surveys in the Mattole and draw attention to homestead and ranch roads as significant sediment sources. They have developed many programs over the years including sediment reduction through road upgrades and decommissioning, forestland and riparian planting, stream bank stabilization, water conservation and community education. Sanctuary Forest has worked primarily to protect habitat through land

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and conservation easement acquisition and was instrumental in the formation of the Upper Mattole River and Forest Cooperative. In the late 1990s a new problem arose for Mattole communities and fisheries. In the summer and fall of 1999, low streamflows were observed by many residents and fisheries groups. Longtime residents couldn’t remember ever seeing the river so low. Fisheries groups and residents were very concerned about the impacts of inadequate streamflows on the already threatened salmonid populations. Residents were also concerned about the impact of low streamflows on water quality and the inadequate water supplies needed to meet basic human needs. Over the course of the next 5 years, low streamflows would become an annual problem with the most extreme conditions observed in the Mattole Headwaters. The headwaters of the Mattole is the primary habitat for over summer juvenile coho and steelhead.9 When water levels get extremely low, thousands of juvenile fish die as pools dry up or become very shallow, making the fish easy prey for raccoons and other natural predators.10 As flows diminish, water quality for healthy juvenile salmonids is also compromised. Dissolved oxygen levels can drop below minimum requirements and result in poor feeding and weak juveniles with low survival potential.11 Scott Downie and Gary Flosi of the local Department of Fish and Game are very concerned about the threat of Mattole low flow conditions to salmonid survival. Scott Downie perceives the low flow condition to be the lightning rod issue that, if not solved, will overshadow all the fish habitat improvement work of the last 20 years.12 The Mattole low flow problem is recognized in the North Coast Watershed Assessment Program (NCWAP) report on the Mattole watershed,13 as well as in the Recovery Strategy for California Coho Salmon.14 People in the Upper Mattole have also been impacted by the low flow problem. Low flows result in poor water quality for human use. The accompanying rise in water temperature causes increased growth of algae and microorganisms. Stagnant pools turn dark in color and begin to putrefy with decaying organic material and small animals (such as rodents) that have fallen in. In 2002 and 2004 some families completely ran out of water. Several families were able to purchase water that could be hauled in. Other families were unable to utilize this option because of inaccessibility by water trucks or because of the expense involved. Gardens had to be abandoned and basic daily water needs for cleaning, cooking and indoor plumbing met through gallon jugs and help by neighbors. Tensions in the community ran high and there was a tendency to blame upstream water users for the water shortage. MATTOLE HEADWATERS LOW FLOWS-HISTORICAL CONTEXT AND CURRENT CONDITIONS Sanctuary Forest and the Mattole Salmon Group engaged hydrologist Randy Klein to conduct a preliminary hydrology assessment of the Mattole low flow problem. Randy Klein analyzed the Mattole low flows using the 2002 NCWAP report with Petrolia flow analysis for 1951-200015 and USGS Ettersburg and Petrolia flow data for 2001-2003.16 In his report,17 Randy characterizes the current low flow pattern as far outside the predicted natural variation, based on 50 years of low flow data from the Petrolia station. The last 17 years represent lower than average low flows for the 50-year record. The low flows have been the most acute from 1997 to

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the present, with most severe low flows occurring in 2001, 2002 and 2004. Randy Klein analyzed the 2001-2003 low flow seasons using frequency estimates (from the 2002 NCWAP report) based on Petrolia low flow data from 1951-2000. The probability of such low flow levels occurring was estimated at once every 400 years for 2002 and once every 80 years for 2001.18 2003 was closer to, but still below, the mean 7-day low flow of 28 cubic feet per second (cfs) from the 50-year record.19 The lowest recorded streamflow at the Petrolia station was 14 cfs on September 26, 2002.20 Sanctuary Forest obtained preliminary USGS low flow data for 2004.21 Comparison of August flows for 2001 through 2004 at the Ettersburg station placed 2004 low flows between 2001 and 2002. The Mattole Headwaters upstream of Bridge Creek has been observed to have the most severe low flow impacts. A quantitative assessment of Mattole Headwaters low flows was determined to be critical for evaluating causes and solutions. Streamflows had not been measured in the Mattole upstream of Ettersburg and no quantitative data existed. During the summer of 2004, Sanctuary Forest and the Mattole Salmon Group undertook a monitoring project to measure streamflows and water quality in the Upper Mattole. Four mainstem sites and one tributary site were selected and measurements were conducted between August 28th and October 8th. The map in Appendix A-1 shows the location of mainstem sites. Randy Klein analyzed the flow measurements for the time period August 28th through September 28th in his low flow report for the Mattole River.22 Two graphs from his report are reproduced as Figures 11 and 12 on page 11 of this report. The results were startling, with much lower flow rates than expected and a high rate of decline in the mainstem over the 9-day period from August 28th to September 6th. The site above Stanley Creek (MS2)—with the highest measured flow in the headwaters mainstem on August 28th—was only 0.16 cfs (equivalent to 72 gallons per minute, or gpm). The USGS flow measured at Ettersburg was 4.6 cfs (approximately 29 times higher) during the same time period.23 The flow at site MS2 dropped by a factor of four in 9 days and within 3 weeks was reduced to only 0.006 cfs (2.1gpm). An average shower uses 2.3 gpm. The entire river flow upstream of Bridge Creek was less than one average shower by September 21st. Flows continued to decrease for all the mainstem sites through September 28th. Two of the sites (MS3 and MS4) near the Whitethorn Junction stopped flowing by September 21st. The landowner at site MS4 has observed the river stop flowing every year since 1999.24 Flows improved significantly at two of the sites (MS2 and MS3) between September 28th and October 8th before the first rain. The nights had become quite cold and the deciduous trees had turned color with the fall weather. The increase in flows is likely the result of lower evapotranspiration as the deciduous trees transition into dormancy. Low flows cause dissolved oxygen levels to drop. Salmonids can survive with dissolved oxygen as low as 3 mg/L but impairment can begin to occur at 6 mg/L.25 Low oxygen levels can cause metabolic stress and increased susceptibility to disease. In 2003 the Mattole Salmon Group monitored dissolved oxygens biweekly between early August and late October at ten pools.26 On September 8th, 2003, dissolved oxygens were adequate with levels above 6 m/L in all pools. Dissolved oxygens decreased over the next 6 weeks, dropping

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below 6 mg/L in five pools by September 30th and all but two pools by October 21st. Three pools dropped below 3 mg/L by October 21st. Streamflow measurements were not undertaken for this project. Unfortunately in 2004 funding was available for only one day of dissolved oxygen monitoring. Streamflows were measured on the same day to allow correlation of streamflows with dissolved oxygens. The Mattole Salmon Group measured dissolved oxygens on September 11th at the four mainstem sites. The measurements ranged from 3.4 – 8.6 mg/L and were lowest in the pools with the lowest flows and at deeper levels. Dissolved oxygens tended to be higher at the surface and tail end of pools. The streamflows ranged from 0.001 cfs at site MS4 to 0.02 cfs at site MS2. The dissolved oxygens measured on September 11th 2004 are in the range at which impairment can occur. In 2003, dissolved oxygens decreased to stressful levels (and in some cases potentially lethal levels) for juvenile salmonids, even though streamflows were higher than in 2001, 2002, and 2004. Sanctuary Forest and the Mattole Salmon Group conducted a survey of the Upper Mattole mainstem with the Department of Fish and Game to observe and evaluate flow conditions, water diversions and fish passage barriers. This survey on August 23rd and 24th 2004 encompassed the river reach from the headwaters, just upstream of Ancestor Creek, downstream to Bridge Creek. The survey was very instructive and provided a qualitative assessment of flow conditions and a quantitative assessment of pump density.

The DFG survey results indicate that there are currently 50 pumps in the Mattole mainstem between Ancestor Creek and Bridge Creek.27 The density of pumps is very low upstream of Stanley Creek. The highest density reaches were Stanley to Mill Creek, Vanauken to McKee Creek, and McKee Creek to Bridge Creek, with approximately 10 pumps in one river mile for each reach. Most of the pumps had inlet screens that offered some juvenile salmonid protection. A mesh size of 3/32 inches or less is needed to prevent uptake of juveniles.28 The map showing pump location and density is located in Appendix B. The river was observed to be highly variable, with reaches containing deep cold pools and healthy flows interspersed with highly aggraded reaches with shallow, warm and low flowing water. Only two small subsurface areas were observed on this date and they were located just upstream and just downstream of the one-lane bridge below Helen Barnum Creek. By September 11th, only two and a half weeks later, the size of these subsurface areas had increased dramatically and adjacent pools containing juvenile fish had completely dried up. The observed tributary flows may provide some insight regarding the factors influencing the low flow problem. All of the west side creeks (except Ravens Creek) had much better flows than east side creeks. All of the east side creeks downstream of Dream Stream (except Sinkyone/Buck Creek) were either barely flowing or flowing subsurface. Even Vanauken Creek with a large drainage area and no residential development was flowing very slowly. Sediment deposits were observed in most of the east side tributaries.

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Figure 11. Low flows at five sites in the Upper Mattole River, 2004

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Site Codes (in downstream order):MS1 = mainstem below Helen Barnum CreekMS2 = mainstem above Stanley CreekMS3 = mainstem below McKee CreekMS4 = mainstem above Bridge CreekSCR = Sinkyone Creek (eastside tributary)

downstream

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Figure 12. Late summer flow recession in the Upper Mattole River, 2004.

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Sinkyone/Buck Creek was the only east side creek with good flows and it continued to flow well throughout the remaining dry months. This creek has two recharge ponds approximately one mile upstream from the confluence that are likely contributing to the improved flows. The measured flows for Sinkyone/Buck Creek are shown graphically in Figure 11 on the preceding page. On September 28th the measured flow at Sinkyone/Buck Creek was higher than any of the mainstem sites. The important question of minimum flows required to maintain adequate water quality needs to be further researched. Observations based on measurements from the 2004 low flow season suggest that streamflows of 0.2 cfs at site MS2 and 0.15 cfs at MS4 may define the threshold below which water quality declines rapidly and becomes inadequate for both fish and people. This conclusion is supported by visual, qualitative observations: As streamflows dropped below 0.16 at site MS2, the Mattole Headwaters changed dramatically from a river with connected (albeit slowly flowing) pools to a river with many subsurface reaches and disconnected stagnant pools. Looking at dissolved oxygens alone could lead to the conclusion that streamflows ten times lower than the 0.2 cfs threshold would likely cause impairment but not death to juvenile salmonids. When the streamflow dropped to 0.02 cfs at site MS2 on September 11th, dissolved oxygen levels were still above the level considered lethal. However, by this time thousands of salmonids had already perished as pools either dried up completely or shrank, making them easy prey to natural predators. In other words, water quantity (streamflows) may be a better predictor of salmonid survival than dissolved oxygen in the Mattole Headwaters. POSSIBLE CAUSES OF THE LOW FLOW PROBLEM The possible causes of the low streamflow problem are multiple and complex. Climate changes, land use practices (both historic and current) and increased human water use are all important factors to further investigate. Climate Changes Many scientists have researched and documented changes in global climate. Extrapolation of the impacts of global climate change to the Mattole was not undertaken for this report. Important climatic factors that were investigated include annual precipitation and seasonal precipitation patterns. According to the 2002 NCWAP report, annual precipitation does not appear to be a factor influencing low flows. The historic data within the basin contain many short-term dry and wet periods. However, based on analyses of rainfall since the mid-1930s, the NCWAP report concludes that there are no discernable long-term trends in annual rainfall.29 Qualitative observations suggest that changes in seasonal precipitation patterns may be an important factor influencing Mattole River stream flows. To many people who have lived in the Mattole for 30 years or more, it seems that the rains often stop earlier in the spring and come later in the fall than they used to. USGS staff have also observed changes in precipitation patterns.30 They describe the winter rainfall season as more compressed than in past years. Randy Klein evaluated the relationships between spring rainfall and late summer low flows in his Mattole low flow report. In this preliminary analysis, summer and early fall rainfall appeared to

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be more important to low flows than late winter and spring rainfall. However, a comparison of spring rainfall for the years 2001-2003 indicates that uncommonly high spring rainfall in 2003 was likely responsible for 2003 improved flows.31 Further evaluation of rainfall data needs to be done to establish quantitative relationships between seasonal precipitation and streamflows. Changes in summer temperatures could also be a factor influencing Mattole streamflows. Hotter summer temperatures can increase water evaporation and evapotranspiration of riparian vegetation, resulting in lower streamflows. Sanctuary Forest was unable to obtain historical summer temperature data, so no analysis is included in this report. In discussion with longtime residents, historic summer temperatures have been described as hotter than they are now. An analysis of current and historic summer temperature data is needed to evaluate this potential factor. Land Use History The heavy logging that occurred in the 50s and 60s left significant impacts on the Mattole Basin that could be contributing to the low flow problem. Sedimentation has been recognized as a major problem by long time residents and fisheries groups. The first study of Mattole River sedimentation was summarized in a report by the Mattole Restoration Council titled “Dynamics of Recovery” in 1995. They determined that roads are the principal human-induced cause of sedimentation. They estimated a total of 3,310 miles of roads in the Mattole Basin, with 2,800 miles consisting of abandoned logging roads. Only 75 miles are paved county roads; the remaining 435 miles are unpaved roads including county, residential, ranch, logging, and BLM access roads. 32 The high sediment loads in the Mattole have been identified as a key barrier to recovery of endangered salmonids, primarily due to the impact of sediment on spawning beds. Sediment can impact streamflows by filling in channels, causing streams to flow subsurface. When streams flow subsurface they no longer provide habitat for aquatic species. According to hydrologist Randy Klein, another effect of sediment deposition is the elevation of the water surface within the channel, potentially causing a reversal of the ground water gradient from one that slopes toward the channel to one that slopes away from the channel.33 If the gradient causes the water to flow out of the streambed and into the adjacent aquifer, it is likely that less water will reach downstream adjoining tributaries and the river. Another impact of sedimentation observed on the Mattole mainstem is the loss of many large pools. Longtime settlers remember many deep swimming holes that are filled with sand and gravel now. The loss of these pools results in less water and less habitat. The pools are particularly important for providing habitat in low flow years when the shallow reaches dry up or flow subsurface. The heavy logging of the 50s and 60s also resulted in loss of riparian shade on many tributaries and river reaches, particularly downstream of Ettersburg. Higher evaporative losses due to inadequate shade could be a factor. In the Mattole Headwaters, shade is not an issue. Instead, the growth of brush and young trees is very dense, possibly the highest density since the mature

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forests were logged. Evapotranspiration from the increased vegetation density may contribute to the low flow problem. Population and Water Use Increases US census data for the Mattole River Basin shows a total population of 1,132 in the year 2000.34 A comparison of 1990 and 2000 data for the Mattole region southwest of Honeydew (95589 area code) shows a population increase of 250 in the last 10 years. This represents a 34% increase for this area. Comparisons could not be made for earlier years due to changes in census areas and methodology. Water use per person has increased significantly in the past 40 years with changes in lifestyle. In Whitethorn during the 1950s and 1960s most families depended on gravity flow water from springs and small creeks. These water sources were very limited and households were managed with very little water. My family used a spring that would often dry up in late summer. We used an outhouse in the summer and a ringer washer that could do 10 loads of wash with the same water. The bathwater was shared and reused by all six kids. Our garden was small and in dry years we quit watering in late summer. I don’t remember knowing anyone who had a lawn in the Whitethorn area. The only irrigated fields were at a sheep ranch in Ettersburg. Even the orchards were unirrigated in those days. (T. McKee) Since the 1970s, most of the families in the Whitethorn area are able to afford pumps to supplement their water use and withdraw water from nearby creeks or the river. Modern lifestyles most often include indoor plumbing and automatic washing machines and dishwashers that are not water efficient. Many families enjoy gardening and landscaping and some maintain lawns. Most of the orchards are also irrigated. If population and water use continue to increase, it is expected that low flow impacts to households will become more widespread affecting more households in the Mattole Headwaters as well as downstream communities. POSSIBLE SOLUTIONS TO THE LOW FLOW PROBLEM ─ VOLUNTARY MEASURES In evaluating the options for improving streamflows it is helpful to look at all potential causes and determine which causes can be controlled. Climate changes could be significant but cannot be controlled. The long-term effects from logging history such as sedimentation and loss of riparian shade are significant. The restoration work of sediment removal and tree planting is ongoing, and it may take decades to realize the benefits. This leaves human use as the factor that can be most readily modified, and changes in human use can result in immediate benefits to streamflows. Water Conservation and Management Practices Water use in the Upper Mattole has increased in the last 20 years and changes in water use could help solve the low flow problem. The climate of the Mattole is one of heavy rainfall over the

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winter months and hot, dry summers. The low flow conditions occur in late summer and fall after 2-3 months with no rainfall and hot weather. The Mattole climate offers the opportunity to store water from heavy winter rains for use during the driest months of August through November. If enough water could be collectively stored for the dry season, water withdrawals from the river, tributaries and springs could be discontinued or greatly reduced during the dry months. In order to calculate the potential benefit of water storage and cessation of water withdrawals during the dry months, an estimate of total water use for the Mattole Headwaters is needed. For the purposes of this study, the Mattole Headwaters is defined as the Mattole Basin upstream of Bridge Creek. Sanctuary Forest prepared water use estimates based on the 2002 NCWAP report with adjustments to reflect local water use practices. The population for the year 2004 is estimated at 300 with 100 households. Water use per household is estimated at 900 gallons per day (gpd) and 90,000 gpd for total residential use in the Mattole Headwaters. The daily use estimates were calculated using the following assumptions for each household: three people using 75 gpd per person; 475 gpd for gardens and lawns; and 200 gpd for leaks and overflow. Agriculture, schools, businesses, public agencies and non-profits also use water. The rough estimate for agriculture is 25,000 gpd and includes all large-and small-scale agriculture. Businesses, schools, public agencies, churches and non-profits groups are estimated to use a total of 15,000 gpd. The estimated total water use per day for households, businesses and others is 130,000 gallons. Thus, with adequate storage and water conservation, it is possible that streamflow in the Mattole Headwaters could be increased by an amount up to 130,000 gpd (0.20 cfs). The water could be left in the river and contribute to healthy flows instead of being withdrawn for human use. When river flows become low, water use in the Upper Mattole becomes very significant. In order to determine the impact of water withdrawals on streamflows, Sanctuary Forest compared human water use estimates with streamflow measurements. The measurements from site MS4 (just upstream of Bridge Creek) were used because this site was located to measure the downstream end of total human use for the Mattole Headwaters. The streamflow at site MS4 on August 28th , 2004 was only 0.1 cfs, or one-half of the estimated water use in the Mattole Headwaters. It may be more instructive, however, to consider water use as a percentage of streamflow. Seen in this way, water use represented 66% of the estimated unimpaired flow (i.e. without human use) at site MS4. The estimated unimpaired flow at site MS4 on August 28th was 0.3 cfs. As discussed earlier in this report, streamflows declined at a high rate over the month of September, and site MS4 dropped to zero flow by September 21st. Water quality was adequate on August 28th but deteriorated as flows dropped. Water quality observations over the course of September suggest that minimum streamflows of 0.2 cfs at MS2 and 0.15 cfs at MS4 could be sufficient to maintain adequate water quality and quantity for fish habitat. Thus, water storage and conservation on a community-wide level could more than double the flow during low flow months and significantly improve water quality and quantity. Water Storage-Tanks and Ponds In 2002 and 2003, concerned members of the community along with Sanctuary Forest, Mattole Salmon Group, and Mattole Restoration Council held two public meetings to discuss the low flow problem and develop solutions. The meetings were focused on measures that individual

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landowners, businesses, farms, and public agencies could take to reduce their water usage during the dry months. Water storage for use during the dry season was recommended because it would reduce water withdrawals during the critical months. Water conservation was also emphasized and methods for increasing household and garden water efficiency were recommended. Water storage was researched to determine the amount of water an average household would need to store and to evaluate options for storage. Based on limited research, water storage for 3.5 months, assuming a water-efficient, two-person household and an 800 square foot garden, was calculated at 23,000 gallons. This includes 10,500 gallons for household use (based on 50 gpd per person), 10,000 gallons for a water-efficient garden and 2,500 gallons of fire safety water.35 The two main options for storage are tanks and ponds. Ponds may be a viable option for small farmers with large irrigation needs. If more than 50,000 gallons of storage is required for irrigation, a pond would likely be more economical than tank storage. However, ponds raise other potential concerns, including erosion, leaks, and non-native species habitat. They also have rigorous permitting requirements. Household use cannot be supplied by pond water because of water quality issues. Large 25,000- 66,000 gallon Australian Pioneer tanks are recommended because of their cost efficiency. They consist of a frame with galvanized metal sides, a dome roof, and an inner liner. For storage volumes greater than 10,000 gallons they cost less per gallon than plastic tanks. The cost per gallon ranges from $0.38 for a 25,000 gallon tank to $0.29 for a 66,000 gallon tank. These costs include tank prices (plus shipping) of $7,000 to $15,000, installation ranging from $600 to $1,200 and pad construction costs of $2,000 to $3,000. Installation and pad construction costs vary by site and all costs listed above are estimates. Tank costs are dependent on the exchange rate and steel prices and are expected to increase. RMI plastic tanks with 5,300 gallon capacity cost $0.43/gallon. Pioneer tanks have some special considerations. They have a diameter of approximately 30 feet and require a flat site and a prepared base with a layer of rock and a top layer of sand. Shipping from Australia requires 45 days. They must be partially filled immediately after assembly to prevent them from blowing away.36 Water savings from water storage will vary depending on average usage and amount stored. The minimum recommended storage amount for a two-person household is based on the water-efficient model and equals 23,000. The storage amount based on standard use37 for the same size household and garden would be 55,000 gallons including 2,500 gallons of fire safety water. A larger garden, orchard or livestock would require additional storage. Water Conservation and Efficiency

Water conservation measures are also important for reducing water withdrawals during the dry season. Water waste associated with tank-filling systems and piping is estimated to be significant. Many tank filling systems do not have automatic shutoff valves and water overflows on the ground after the tank fills until someone remembers to shut off the source. Water waste could be significantly reduced by installation of automatic shutoff valves or overflow piping back to the source river, tributary, or spring. Water system leaks can also contribute significantly to water waste. Exposed pipes are subject to big leaks from animal bites. Joint leaks are common from expansion and contraction of pipes during cold weather. A single dripping faucet can lose

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18 or more gallons in a day. Annual system maintenance to repair leaks could reduce water waste significantly.

Water-efficient gardening can significantly reduce water use. Average standard water use for an

800 sq ft garden is 150 gpd and 15,500 total for 3.5 months, based on State Water Resources Control Board (SWRCB) suggested water use.38 French Intensive Gardening can reduce water use by half.39 Other water-efficient gardening techniques include drip irrigation, mulching, soil preparation, timing of watering and methods to avoid overwatering. Plant selection and timing of planting is also important for both gardens and landscaping.40 Dry farming in the Mattole Headwaters is currently being tried for potatoes with good results.41

Household water conservation measures include leak repair of household fixtures and replacement of standard fixtures with water efficient fixtures. Low-flow shower heads and faucet aerators are very inexpensive and help conserve water. Water-efficient toilets and washing machines can make a big difference in water use. The potential water savings from water conservation are roughly estimated based on the overall difference between water-efficient households and gardens versus standard usage. Total water use is estimated at 195 gpd for the water-efficient model and at 500 gpd for the standard usage model. Both models are calculated for a two person household and an 800 sq ft garden. Water conservation savings are estimated at 305 gpd (61% of standard use) and 32,000 gallons per household over a 3.5 month period. It is important to note that the water savings from water conservation can be as high as the water savings achieved through tank storage. Water savings from households with standard water use that adapt to efficient use are roughly equivalent to water savings from water-efficient households that utilize storage to discontinue all water withdrawals. While storage along with complete cessation of water withdrawals offers the greatest potential benefit to streamflows, storage may not be feasible for every household. Water conservation measures are economical and within the means of most households. In order to look at potential water savings for the entire Mattole Headwaters, the following calculation based on a combination of storage and water conservation was done. The total water use for households, businesses, and others was estimated at 130,000 gallons per day or 0.2 cfs. If 75% of all water use could be supplied by storage the water savings would be 0.15 cfs. If the remaining 25% of water use could be reduced by 61% through water conservation the estimated savings are calculated at an additional 0.03 cfs. The total calculated water savings (the sum of water storage and water conservation savings) would equal 0.18 cfs—a 90% reduction in total water withdrawals. Water Rights in the Mattole An understanding of water rights is important for evaluating solutions to the low flow problem. Some of the measures that have been used to address low flows on other rivers are only effective if most of the rightholders have appropriative rights. Voluntary water storage and conservation programs require consideration of each participant’s water rights to ensure that individual water rights are not jeopardized. Sanctuary Forest engaged water law attorney Robert Donlan to assist with writing the following section on water rights, and to evaluate the legal implications of all voluntary and compulsory measures to improve water flows.

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The majority of water diversions from the Mattole River Basin appear to be under riparian basis

of rights. Riparian rights are rights to surface water withdrawal from a stream that passes through or adjacent to the rightholder’s property. Estimates based on State Water Resources Control Board (SWRCB) records of Mattole River Basin surface water rights indicate that approximately 88% (355 out of 405) Mattole households have not filed water claims.42 These households are diverting water under the basis of riparian rights, pre-1914 appropriative or are illegal diversions. The SWRCB 2000 list of surface water rights for the Mattole River Basin included a total of only 50 claims. Of these claims, 40 are appropriative permits or licenses, 3 are small domestic registrations, and 7 are pre-1914 appropriative or riparian claims. In the Mattole Headwaters, there are approximately 7 appropriative claims listed, leaving an estimated balance of 93 households that have not filed with the SWRCB and are likely operating with riparian rights.

California Water Rights

The California Constitution says that the state’s water resources belong to all Californians. “Any citizen may use water for beneficial purposes by obtaining a water right.”43 “A water right, although a property right is not ownership of water. In general, the possession of a water right is an opportunity to share in the responsible development and beneficial use of a public resource.”44All water rights are limited to amounts reasonably necessary for the intended use and do not extend to wasteful or unreasonable use. The SWRCB administers the state’s water quality and water rights functions. The California Department of Fish and Game (DFG) reviews all SWRCB water appropriation permit applications to determine the need for terms and conditions to protect fisheries.45 California recognizes three classes or types of water rights: riparian rights, appropriative rights (including “pre-1914” and “post-1914”), and prescriptive. The three classes of rights are described below. The California Water Acquisition Handbook46 is the primary source with important additions by Robert Donlan.

Riparian rights are attached to the smallest tract of land that abuts a natural watercourse and held

by the landowner through ownership of riparian land. Riparian land must be within the same watershed as the watercourse. Riparian rights attach only to the natural flow within a watercourse and do not include imported waters or water foreign to a watercourse. Unless adjudicated, a riparian right is typically unquantified, and entitles the landowner to a “correlative” portion of the natural water supply, to be shared with other riparian users. In times of shortage, all riparian users on a watercourse must curtail diversions and share the common supply. Riparian rights are generally superior in priority to appropriative rights, and in times of shortage, appropriators must cease diversions before riparians will be required to reduce diversions. Riparian use must be “reasonable” (i.e., non-wasteful) and “beneficial” (i.e., a valued use) and cannot be lost or reduced as a result of non-use of water.

Proper riparian diversion and uses can be made without a permit from the SWRCB. The Water

Code requires riparian right holders to file a Statement of Water Diversion and Use with the SWRCB to assist state documentation of riparian water use, but there is no penalty for non- filing. A riparian water right is for direct diversion and use from a stream, and does not include the right to “store” or hold water for more than 30 days before use. Storage for longer than 30

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days requires a SWRCB permit. When riparian lands are subdivided, parcels that are severed from the adjacent water source lose their riparian rights unless there is an express reservation of water rights for the non- adjacent parcels.

Appropriative rights differ from riparian rights in that they are severable and distinct from

ownership of land, and use is not limited to riparian lands. The basic elements of an appropriation are (1) intent to divert and take water under control, and (2) application of the water to continuous, reasonable and beneficial use. The relative “priority” of the appropriative right is based on the application date, consistent with the principle of “first in time, first in right.” An appropriator is entitled to the full quantity of water specified under the right before “junior” appropriators may exercise their rights, but appropriative rights are generally inferior (or “junior”) in priority to riparian rights. Like all water use in California, after diverted under an appropriative right, the water must be used reasonably and beneficially. Appropriative rights may be lost, in whole or in part, after 5 years of non-use, and may also be abandoned.

An appropriative water right can take two forms: pre-1914 and post-1914. Post-1914

appropriative rights can be obtained by application to, and permit from, the SWRCB; once the appropriation is complete, the permittee may request a license from the SWRCB. The issuance of a permit typically involves a public review process. The permit defines the scope of the appropriative water right, including the quantity and rate authorized for direct diversion or diversion to storage, the point of diversion as well as the purpose of water use. The permit may also contain other terms and conditions of use, including instream flow or “bypass” requirements. SWRCB approval is required to change the place or purpose of use, or to change or add a point of diversion. The SWRCB maintains continuing jurisdiction over permits and licenses, and has broad authority to impose additional conditions on a permit or a license, including conditions for the protection of fish and wildlife resources.

Pre-1914 appropriative rights are appropriations that were perfected prior to the effective date of the Water Commission act, which have been maintained by continuous use. Pre-1914 rights fall outside the authority of the SWRCB. The purpose and place of use, and points of diversion may be changed, provided that the change does not cause injury to other water users. Pre-1914 rights were acquired by notice or taking other action that would put a reasonable person on notice of the intent to appropriate water for reasonable and beneficial uses. The Water Code requires pre-1914 appropriators to file Statements of Water Diversion and Use, but there is no penalty for failure to file. Prescriptive rights are different from riparian and appropriative rights, in that they are acquired by continuous and open unauthorized uses of water for 5 or more years. Prescriptive rights originated from conflicts between riparian and appropriative uses where an appropriator sought to protect its appropriation against a new riparian use. The theory behind the prescriptive right is that, if an appropriative use is “open, notorious, and adverse” to a riparian’s right, the riparian has been put on notice and may take action to protect the right against prescription. Prescriptive claims to water are suspect, and the courts have historically rejected claims of prescriptive rights.

Landowner Agreements for Streamflow Protection

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Landowners in the Mattole watershed could make a long-term commitment to the health of the Mattole River by reducing or eliminating dry season water withdrawals and dedicating the saved water to instream flows. A cooperative community undertaking of this magnitude may require an organizational structure and mechanisms for protection of conserved water. On the Scott River a non-profit organization is being considered to administer a “water trust” to lease water from farmers for instream flows. The goal of the water trust is “To foster transactions which will provide improved stream flow for salmon and steelhead at critical periods and locations in the Scott River system by providing fair compensation to water rights holders for the temporary or permanent instream use of their water rights, based on the foregone value of the applied water.”47 This program has identified the following preliminary tasks: identify key river reaches to improve flows; develop agreements with landowners to obtain water for flows; determine legal mechanisms for flow protection; facilitate permitting requirements; monitor outcome of water flow agreements; and generate funds for the program through public and private sources.48 In the Mattole watershed a similar organization could be formed or an existing non-profit could serve this function.

Historically, the California Water Code has allowed for a range of “beneficial” uses of water including agriculture, mining, urban development and sustenance and industrial uses. Prior to 1970 development often occurred without consideration of impacts on fish and wildlife. In the 1970s the Legislature responded to this concern by passing new laws that forced water users to consider impacts of water projects and diversions on the environment. California water law had no formal mechanism to dedicate water to environmental uses prior to 1991. In 1991, the state amended the California Water Code by adding Water Code section 1707, which permitted the transfer and dedication of all or part of a water right specifically for environmental purposes.49

Participants in voluntary water conservation and fishery enhancement programs require assurances that their water rights will not be jeopardized. Depending on the type of water right, a legal mechanism may be required to dedicate water to instream flows while protecting individual water rights. Several mechanisms may be available for instream flow dedications through a water trust program. A“forbearance agreement,” for example, is where the water users simply forgo diversion of all or a portion of their seasonal water through an agreement with the water trust. A forbearance agreement can stand alone or be incorporated into a conservation easement. Another option is a dedication of water to instream flows utilizing Water Code section 1707. Three mechanisms that could apply to the Mattole are forbearance agreements, conservation easements and 1707 dedications. 50

In a forbearance agreement, a water user contracts with the local water trust to forego withdrawals of water pursuant to the terms and conditions set forth in the contract. The main advantage of a forbearance agreement is its simplicity and efficiency. No formal SWRCB or court approval is required and the terms of the agreement can be structured to fit the needs of the parties. The disadvantages of a forbearance agreement include lack of protection of dedicated flows from downstream users and the risks posed to holders of appropriative water rights.51 Downstream users with riparian rights are not restricted to specified quantities of water withdrawals. If upstream dedications result in increased flows riparian rights holders can legally increase their water use. Downstream users with appropriative rights could also use the increased water flows as long as it does not exceed the total quantity specified on their water right. One

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way to avoid these problems is to notify downstream users in advance and seek their participation or obtain from them a written agreement not to divert the increased flow.52 Appropriative water rights owners are potentially at risk if they participate in forbearance agreements for more than 5 years. If the non-use clause goes into effect the right holder can lose the rights to the quantity of water dedicated through the forbearance agreement. Riparian rights cannot be forfeited by non-use and are not put at risk by forbearance agreements.53 Conservation easements could serve as a type of forbearance agreement with the same advantages and disadvantages with regard to water law. The water restrictions of the easement would be structured to fit the landowner needs and no SWRCB process would be required. There would be no legal protection of the water from downstream users, and appropriative rights landowners could lose their seasonal water rights after 5 years of reducing their seasonal water use as per the non-use clause. Conservation easements are traditionally used when a landowner wants to protect specific resource values of the land in perpetuity. Restrictions that protect resources are developed with a land trust that then becomes the trustee of the restrictions and is responsible for their enforcement and legal defense. The conservation easement is a legal document that is recorded on the property deed. Several landowners in the Mattole have developed conservation easements to restrict logging or residential development that would impact wildlife habitat as well as the aesthetic values of their property. Conservation easements require special consideration because of the permanence of the restrictions, the time and cost of development, and the endowment costs required to monitor the easement in perpetuity. The benefits of a conservation easement include protection of the property resources in perpetuity, and potential tax benefits from the reduction in property value that results from the easement restrictions. Dedications of water utilizing Water Code section 1707 can be used to change or transfer any form of water right for instream uses. The 1707 petition must designate the time, location and scope of transfer. The petition process may involve a background investigation into the validity of the water right that is the subject of the transfer, particularly if the claimed basis of right is riparian or pre-1914.54 The change or transfer will be conditioned to avoid or minimize potential impacts to other water users, the environment or local communities. The petition will not be approved if it increases the amount of water the water user would otherwise have a right to use. The 1707 process requires approval of the petition by the SWRCB along with the accompanying public notice, review period, hearing and fees. The petition fees as of July 2004 were $850, and the expense of preparing and processing the petition can be quite high.55 “Short-term” 1707 instream flow dedications cannot exceed one year and have priority for expedited review by the SWRCB. They can be approved in as little as 45 days and are not subject to the California Environmental Quality Act (CEQA). Long-term transfers are for any period in excess of one year and are subject to the requirements of CEQA. The documentation requirements can range from an exemption or declaration of “no significant environmental impact,” to a full environmental impact report. The approval process can take many months.56

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Minor petitions of three cfs or less follow a more streamlined procedure and can be used for long-term transfers. The fees and application process is the same for minor petitions. The main advantage of minor petitions is that they do not require board review and consequently have a faster approval process.57 In contrast to the forbearance agreement, 1707 dedications provide a legally enforceable basis to preclude others from diverting the conserved water. However, there is significant uncertainty in the law regarding how a 1707 dedication affects downstream water users.58 If upstream dedications result in increased flows, for example, riparian rights holders may be legally entitled to increase their water diversions. Downstream users with appropriative rights may also be entitled to divert the increased water flows as long as their total diversion does not exceed the total quantity specified on their water right. However, if the downstream user has not used their entire allotment for more than 5 years, then their right might be reduced through non-use and the additional flows of water could not be legally diverted. If the entire allotment had not been available because of insufficient streamflows, then the downstream user may be entitled to divert additional water up to the amount of his original allotment.59 SWRCB staff have stated that seniority of water rights is a determining factor. 60 If the downstream user has a junior water right they would not be allowed to divert the dedicated water. Appropriative rights in most cases are junior to riparian rights. Seniority of rights is based on the date the right was obtained. Most riparian rights originated when the original patent parcels were created. To the extent a 1707 petition is pursued in the Mattole River, focused discussions with SWRCB staff and downstream water users will be necessary to address these issues.61 According to SWRCB staff, new appropriative rights would be affected the most by 1707 dedications. The SWRCB is working on a flagging system that would indicate the presence of a 1707 on a stream reach. If a new appropriative-rights permit application was filed for that reach, the 1707 dedication would come up indicating that the 1707 water is not available for appropriation by others. It would also earmark the entire stream for low streamflow issues and initiate an inquiry of water availability prior to granting approval of new water rights.62 Appropriative right holders with 1707 dedications are protected from loss of water rights by non-use. The appropriative rights water user is exercising his right by dedicating a specific quantity of the allotted water to instream flows.63 A 1707 dedication can be accomplished by an individual landowner without the involvement of a water trust. The landowner can work directly with the SWRCB to file a petition and develop all of the required supporting data. The assistance of an attorney will likely be required to assess the existing water right and address other legal issues.64 Alternatively the landowner can participate in a voluntary program through a water trust or similar organization. In this scenario, the 1707 water dedication could be held by the water trust. The landowner could donate, sell or lease its seasonal water rights to the land trust. If the water rights are donated the seller may be eligible for tax deductions based on the fair market value of the water as a tax deduction. 65 (A tax advisor would need to be consulted to determine the availability and extent of such a deduction.) The water trust would work with the landowner to determine if the 1707 is the best option for achieving the water conservation goals. If so, the

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water trust could assist in preparation of the SWRCB petition, including development of the water rights opinion and supporting information. The water trust could also conduct an appraisal process to establish the value of the water. There are many appraisal methodologies, including comparable sales, cost or income approaches. The comparable sales methodology involves finding similar transactions in terms of type and priority of water right, location, time of sale and quantity of water involved. Cost methodology is based on how much public agencies and private entities are currently spending to develop additional water supplies. The value of the water right is determined based on the cost of its replacement with another source. The valuation would also include the costs for complying with all applicable environmental laws, such as CEQA. The third appraisal method involves the income approach and is based on the potential income that could be generated through use of the water. The appraiser would determine what someone would currently pay for the income that could be derived from reasonable and beneficial use of the water right.66 Once the 1707 transfer is approved the water trust may seek long-term enforcement protections for the acquired instream flows. For example, a conveyance document (a deed) could be recorded with the appropriate county office. Failure to properly record the deed could result in legal disputes over the water rights should the land be acquired by another party. After documentation is complete the water trust could take appropriate steps to protect the water right from infringement or misuse.67 The length of the agreement needs to be considered. The low flow problem is unlikely to diminish unless the climate changes. As the population in California grows, it is predicted that population in the Mattole watershed will increase. Water conservation agreements that ensure long term protection may provide the greatest benefit to future habitat. Conservation easements establish habitat protection in perpetuity. The restrictions are recorded on the deed and transferred with the property when sold. Unrecorded forbearance agreements would most likely be limited to the current landowner. A permanent, recorded sale or donation of a water right to a water trust for dedication to instream flows would not be affected by changes in land ownership. Monitoring of Landowner Agreements The voluntary participation of a landowner in a water conservation program would include monitoring regardless of the mechanism selected to protect the water. A landowner agreement for water conservation involves several issues. The landowner will need to make improvements for water storage or to improve water efficiency or both. The improvements will need to be maintained to function properly. Problems will probably arise, such as leaks that drain stored water, or longer than expected dry seasons requiring more water than was planned for and stored. Education on management of water storage tanks is very important. Tanks need to be plumbed with a leak safety system so that they will not be drained in the event of leaks. Timing of filling is also critical. Filling of tanks during the dry season as a result of leaks, increased water use or late installation could have major adverse impacts. Withdrawals of thousands of gallons in one day could completely drain the source pool during the dry season when flows are minimal. Conservation easements are typically monitored annually. Monitoring of agreements for water conservation would most likely occur twice per year: spring monitoring to ensure that water

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system maintenance and water conservation systems are in place for the low flow months, and fall monitoring to review water meter records and determine if the objectives are being met. The monitoring would provide feedback on the success of the water management plan. It would indicate the need for additional water conservation measures and/or restriction modifications. Permitting and Compliance Issues Water Storage Permits Because riparian rights do not authorize storage for more than 30 days, an SWRCB permit is required if water will be stored for longer than 30 days as part of the water management program. There are no exceptions for storage of small water volumes.68 Permit applications can be obtained from the SWRCB. The registration for small domestic use appropriation covers storage not to exceed 4,500 gallons per day by direct diversion or 10 acre-feet equal to 3,258,510 gallons per annum by storage. All applicants are required to send a copy of their application to DFG first. DFG reviews the proposed project and supplies in writing either (1) terms and conditions under which you may divert water for storage or (2) a determination that additional conditions are not required.69 There is no public process for domestic use applications. If the application is approved, the SWRCB will issue a permit specifying general and specific conditions with which you must comply. The filing fees are $250. The registration must be renewed every 5 years at which time a report of use and a renewal fee of $100 must be submitted. A registered right may be lost by non-use of the water for 5 consecutive years, revocation because of false statements, or failure to renew the registration or comply with registration conditions.70 Landowners with appropriative rights may require new storage permits unless the original permit includes storage. Appropriative rights permits define the quantity of diversion and/or storage as well as the allowable place and purpose of use of the water. Any change requires a petition for change with the SWRCB and a $100 filing fee.71 DFG staff recommended contacting them prior to filing applications for water storage permits. It was suggested that a sample permit be developed for the Mattole Headwaters that would define the DFG terms and conditions required for water storage. The sample, once approved by the DFG, could be used by individuals and facilitate the permitting process. Examples of terms and conditions include prohibited pumping during critical low flow months and requirements for fish protection screening on pump inlet pipes.72 Enforcement of water storage permits was discussed with SWRCB staff. At this time it is unlikely that landowners would be penalized for lack of permits. Upon discovery of unpermitted water storage, the SWRCB would require the landowner to obtain a permit and would likely allow storage to continue during the permit approval process.73 Taxation of Storage Tanks and Ponds Humboldt County currently does not have any tax exemptions for private property improvements that create a public benefit.74 Storage tanks and ponds create public benefit through improvements to streamflows and fire safety. Mendocino County generally does not tax storage ponds or tanks that are used exclusively for fire safety.75 The MRC Mattole fire safe project is researching tax exemptions for fire safety water storage in Humboldt County. Apparently,

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changes in taxation occur on the level of county planning.76 An important part of planning for responsible stewardship includes a tax plan that offers incentives to private landowners who help protect public resources. Tanks are appraised as property improvements based on “in place value” which includes equipment, shipping, materials and labor as well as value of any contributed labor. The Tax rate is 1% of fair market value. Currently a 42,000 gallon Pioneer tank is assessed at $15,000 resulting in annual taxes of $150. Ponds are assessed based on the amount of excavation and estimated value.77 The tax rates for Humboldt and Mendocino County are the same. Appraisal occurs at the time of discovery. If the landowner notifies the assessors office directly or through an associated permit process the improvement will be assessed in the year it is completed. The assessment will establish a base value for the improvement that all future taxes will be calculated from. If the improvement is discovered in a future year the appraisal will be based on the more recent of the two dates: date of completion or the third back year. Back taxes will be charged for the current year plus a maximum of three back years. If the tank was installed ten years prior and tank costs have increased significantly, the annual taxes will be higher because they will be based on the inflated value.78 Water Enhancement to Supplement Flows Further quantification of human water use and analysis of Mattole hydrology needs to be undertaken to determine if reduced water withdrawals during the dry months will result in adequate streamflows. If the amount of water saved through storage and conservation is not enough, then additional methods of supplementing flows need to be considered. Ideas that have been discussed include recharge ponds, groundwater pumping, reconnecting tributaries, and brush clearing along tributaries. Recharge ponds (as defined among Mattole fisheries groups) consist of small dams high up in the tributaries that store water from the winter rains and slowly release the water over the course of the summer, keeping the tributaries flowing. There are two ponds on Sinkyone/Buck Creek that successfully achieve this function. In the dry years before the ponds were installed, many reaches of the creek dried up. Now, even in dry years the creek runs all summer long. In other areas outside of the Mattole, temporary inflatable dams have been used to achieve a similar purpose.79 The risks posed by recharge ponds are significant. Potential negative impacts include pond erosion and downstream sedimentation, elevated water temperatures, non- native species introduction and fish passage barriers. The permit process for ponds include both the county and DFG. Ponds should be well designed and operated to minimize negative impacts. The inflatable dams may have some advantages over commonly used earth dams. It may be possible to coordinate installation and withdrawal of inflatable dams with fish passage needs. Groundwater pumping from aquifers not directly connected with the river system could be another source of water to supplement stream flows. On the Scott River ground water pumping has been successfully used to augment flows during severe low flow periods.80 We have no local examples with which to evaluate this option. Some considerations include water quality and impacts of pumping on aquifers. The water temperature and mineral composition would need to

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be assessed. (The Mattole has unusually soft water and it is unlikely that wellwater would be unusable because of mineral content.) The pumping of significant volumes of groundwater could have unpredicted impacts on the aquifers and backfire as a solution. Well drilling in the upper Mattole has a low success rate and locating good well sites could be difficult. Many small tributaries in the Mattole Headwaters are filled with sediment and flow subsurface. Old logging roads are the major contributor to this phenomenon. They were often built right in the streambed, burying the creek in some cases with 10 feet or more of soil. Natural siltation also occurs, most often in alluvial floodplains near the confluence of creeks. Sanctuary Forest has excavated buried streams to discover bedrock and renewed water flows even in late summer. Sometimes the sediment removal reconnects the stream to larger tributaries. More often sediment removal will unbury some reaches of the stream, but other downstream reaches are left untreated because of access limitations or risk of causing erosional instability problems. The hydrology of these buried streams should be studied to determine if subsurface flows are reaching main tributaries or are dissipated in the surrounding vegetation. If flows could be increased significantly by reconnecting tributaries, effective methods for implementation can be researched. Solutions could range from excavation of sediment to direct piping of water to a flowing tributary. Dense brush growth resulting from clearcutting and fire suppression has been identified as another potential factor contributing to low flows. Glen Pierson of the Department of Water Resources (DWR) said that brush removal along tributaries has been studied and could increase flows by reducing water uptake from evapotranspiration. The fire hazards of dense undergrowth are a big local concern, and fuels reduction to reduce fire hazards is one program being pursued by the MRC. Possibly brush removal along tributaries could be incorporated in the fuels reduction program and provide streamflow benefits. Funding for Voluntary Measures Funding Available Directly to Landowners The Natural Resources Conservation Service (NRCS) has funding for landowners engaged in commercial agriculture, including farmers’ markets. There is no requirement regarding the amount of agricultural proceeds. NRCS has funding for ground and surface water conservation through the Environmental Quality Incentives Program (EQIP). Water storage conservation projects need to include irrigation efficiency improvements. Applications are ranked based on these improvements. A 50% cost share is required. The project design needs to meet the standards of the NRCS. The NRCS can design the project at no charge to the landowner. Alternatively, landowners can hire their own licensed engineer to design the project and arrange for these costs to be included. Project funding includes installation costs with some exceptions such as permits and electrical hook-ups. NRCS is prohibited from funding residential water conservation programs.81 The United States Fish and Wildlife Service also has funding for projects on private and tribal lands for landowners who wish to improve their land for the benefit of wildlife. Landowners may work directly with the Fish and Wildlife Service or through a conservation organization. Fish

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and Wildlife Service biologists are available to evaluate site habitat restoration potential, design habitat improvement projects and assist with grant proposals.82 Funding Through Non-profit Programs for Private and Public Lands California DFG fisheries restoration grants cover a wide range of fish habitat improvement projects including projects that improve streamflows. Grants can be obtained that will cover all phases of a project from planning to implementation and monitoring. DFG grants will not cover research but will cover habitat assessment needed to plan implementation. The project does not need to fit in one of the existing grant categories. The project proposal needs to be logically developed and include documentation on how it will benefit streamflows as well as how the benefits will be measured. DFG does not recommend projects that require valuation of water. According to DFG staff, valuation of water has proved to be very difficult and complicated. DFG grants could potentially contribute to the costs associated with private landowner water conservation including costs of storage tanks, SWRCB permits, landowner agreements for water conservation, and monitoring.83 Other potential granting agencies for streamflow improvements include Department of Water Resources (DWR), State Water Resources Control Board (SWRCB), California Coastal Conservancy, Wildlife Conservation Board (WCB), National Oceanic and Atmospheric Administration (NOAA fisheries), and County Fish and Game Advisory Commissions. The California Department of Forestry (CDF) may also be a resource. CDF may have fire protection funding that could assist with brush thinning and water storage projects. A new regional water quality grant program, jointly administered by DWR and SWRCB, is currently developing funding guidelines. This program will potentially fund both planning and implementation of projects that protect communities from drought and protect and improve water quality. Examples of eligible projects include: programs for water supply reliability, water conservation and water use efficiency; storm water capture and storage; groundwater recharge and management; non-point source pollution reduction, management and monitoring; and the acquisition, protection, and restoration of watershed lands.84 Funding Through a Resource Conservation District (RCD) RCDs are “special districts” of the state of California set up under California law to be governed locally by their own appointed, independent board of directors. They are not county government agencies but do have close ties to county government. RCDs manage a diversity of resource conservation projects including soil and water conservation projects, wildlife habitat and restoration, control of exotic plant species, watershed restoration, conservation planning, education and many others. RCDs are funded primarily through grants. The NRCS has worked closely with RCDs since the 1930s. The NRCS generally appoints a local RCD conservationist to provide technical assistance to districts and to act as a liaison between the district and federal programs.85 A resource conservation district can help obtain funds and provide technical assistance for conservation projects. The project can achieve higher priority with the funding agencies through recommendation by the RCD.86 Some projects require the participation of an RCD or equivalent organization to obtain funding. Watershed planning projects that will affect community water

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availability and use are an example. These projects require the support of local communities and water agencies. The participation of an RCD helps to establish the support needed.87 Humboldt County has a resource conservation district that encompasses the entire county. The main goal of the Humboldt County RCD is “to provide voluntary cooperative resource conservation assistance to meet the objectives of the landowner.”88 The board of the RCD influences the types of conservation projects that get funding. The board of the Humboldt County RCD consists of mostly agricultural board members, and the projects funded have been primarily agricultural projects in the northern end of the county. Board members are appointed by county boards of supervisors. Boards are meant to represent a broad spectrum of resource conservation interests and perspectives.89 Funding from Private Foundations and Individuals Grants from private foundations and individuals can complement public funding by providing support that is lacking in public funding programs. Potentially, private funding can provide more flexibility to the grantee, multi-year support, and greater potential to fund endowments for long term monitoring and maintenance. Major foundations recognize that philanthropy has an important role in solving the world water crisis. The following example describes a very successful water enhancement program organized by Rahendra Singh in Rajasthan, India, and funded by the Ford Foundation.90An estimated 4,500 johads (earthen reservoirs) have been built in 1,000 villages, all built using local labor and native materials. The johads utilize a rainwater collection tradition that dates back 5,000 years in rural India, which was largely discontinued under English rule. They provide surface water for drinking and irrigation and also recharge dry wells. The villagers provide one-third of the project in labor and the completed johads are community-owned. COMPULSORY AND REGULATORY MEASURES In contrast to voluntary measures, compulsory measures initiate restrictions that affect water use by some or all of the water users. Three measures that initiate water use restrictions are described below. Robert Donlan, water law specialist, advised Sanctuary Forest on the effectiveness of these measures for improving Mattole streamflows. Robert Donlan brings experience from his work assessing options for the Scott River low streamflows. Fully Appropriated River The SWRCB can declare a river fully appropriated. This status would prevent water withdrawals by new appropriative water rights applicants.91 All new water appropriation permits would have to conform to the terms and conditions of the restrictions. New or increased diversions by riparian right holders are unaffected by a “fully appropriated” declaration. According to SWRCB staff, this process cannot be initiated by any person, group, or agency. Instead a protest needs to be filed against an active application for appropriative rights. For example, DFG could protest water rights applications if fish and wildlife are threatened, and the SWRCB would make a decision.92

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If the Mattole River was declared fully appropriated, it is most likely that designation would be seasonal and referred to as “seasonally fully appropriated.” The season could be defined by restricted months or minimum streamflows below which water could not be withdrawn or a combination of the two. In discussion with SWRCB staff, Sanctuary Forest was informed that “fully appropriated river” status would have the most effect on future appropriative rights for small domestic use. Currently, full appropriative rights applications are subject to CEQA and water availability would be evaluated before granting these rights.93 Small domestic use appropriations allow a maximum of 4500 gallons per day and are not subject to CEQA.94 The fully appropriated process can be expensive and time consuming. Currently, the SWRCB fees are $10,000 and the process takes at least 2 years. Documentation is required on why the streamflows are not adequate to support another water user. The required data includes streamflows, fish populations, and flow required to support fish populations. Standards for data collection are high and it has been advised that specific data requirements should be obtained from SWRCB. When a river is declared fully appropriated, the restricted season is defined. If changes in the season length are later requested the SWRCB amendment fees are $10,000.95 Robert Donlan advised Sanctuary Forest not to initiate fully appropriated river status as a first step to addressing Mattole low flows. This status could get in the way of management options and it was recommended that a water management plan be developed first. Robert Donlan suggested that updating the SWRCB records with a complete listing of water use could be a more effective way to restrict seasonal use of new applications. Currently, only 50 water rights are listed for the entire Mattole River, leaving an estimated 355 households unaccounted for. This gives the SWRCB an inaccurately low record of water use. If all riparian and pre-1914 appropriative water users filed statements of water diversion and use, the SWRCB would have a more accurate picture of water use. SWRCB could then more realistically evaluate water availability and use before granting new applications. If the current water use exceeded seasonal water availability, the SWRCB would have a basis to impose seasonal restrictions on new applications.96 Adjudicated Water Rights Adjudication is a process that has been used to resolve disputes among multiple water-rights owners. Adjudications are most common in agricultural communities when water use by upstream farmers has resulted in diminished water availability for downstream farmers.97 Adjudication requires a court order. All existing water rights including riparian, appropriative or other basis of rights are investigated. This process can be initiated with a petition signed by one or more claimants to water of any stream system. If the SWRCB, upon investigation, finds that the public interest and necessity will be served by a determination of the water rights involved, they will grant the petition and proceed.98 At the conclusion of the proceedings, the superior court will enter a decree determining the water rights appurtenant to each parcel. A water master service can be implemented to ensure compliance. This 10-15 year process is expensive. The landowners pay for half of the cost.99

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In past adjudications the court has not included water for environmental purposes. Instead the available water is divided among the water rights holders with no water reserved for instream flows. At this time, it is unclear if the courts would include protection of instream flows as part of the adjudication.100 In the Mattole, adjudication could help provide a structure for future protection of instream flows through quantification of all water rights. The majority of water rights in the Mattole are riparian and therefore unquantified. Once water rights are quantified, 1707 dedications can be developed to protect instream flows.101 However, adjudications are not recommended except as a last resort. The process is adversarial and pits neighbor against neighbor.102, 103 County General Plan Amendment Humboldt County is aware of the low flow problems on the Mattole River from anecdotal sources. The Mattole appears to have the most severe flow problems of any river in Humboldt County. Humboldt County is currently revising the county plan and will look at the low flow issue in terms of future land development. Potential policy will be presented at public meetings during the summer of 2004.104 The county avoids policies that conflict with current landowners water rights. They can designate water conservation areas in which further subdivision and additional use permits would be restricted. In order to get an area designated, requests are made by mail or by attending public meetings. This designation would restrict further subdivision and use permits resulting in a lower density of future water users than would be permitted under the current plan. Requests need to be backed up with data quantifying the impacts of the problem such as: fish populations killed from the low flow, stream flow rates, and oxygen levels. If data is not available, then statements from resource agencies are needed to provide validity to the request.105 All three of the above-mentioned compulsory measures would require community support and documentation of the low flow problem to justify the need for the measure. The only measure that could significantly restrict seasonal water use by existing riparian and appropriative rights holders is adjudication. Most of the water rights in the Mattole are riparian and adjudication is the only measure that would restrict these rights. Amendment of the county plan and fully appropriated river status only affect future water rights. County designation of the Mattole Basin as a water conservation area would decrease the density of all future water users, both appropriative and riparian, through the subdivision restrictions. The fully appropriated river status would only restrict water use by new appropriative rights water users. California Department of Fish and Game Regulations There are DFG regulations that protect fish and wildlife. Two examples that are relevant to the Mattole streamflow problem are the California Endangered Species Act (CESA) (Fish & Game Code sec. 2050), and the Lake and Streambed Alteration Program (Fish and Game Code sec. 1602). CESA prohibits the “take” of an endangered or listed species. “Take” is defined by CESA as to hunt, pursue, catch, capture or kill.106 The Mattole coho are listed as threatened under CESA and therefore entitled to protection against “take.” According to DFG staff, CESA prohibits any action that results in killing of the listed species regardless of intent. Water withdrawals that cause death to listed fish are a violation of CESA. DFG staff acknowledge California water law

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and the entitlement to legally withdraw water in accordance with acquired water rights. However, DFG interprets these rights such that the exercising of water rights cannot violate other laws, such as the laws that protect listed species.107

Fish and Game Code section 1602 states that an entity that intends to substantially obstruct or divert the natural flow, or alter the streambed of any river or stream must notify DFG and submit a project description. The word “substantial” is not defined and would be determined on a site-by-site basis. If DFG determines that the project will not have substantial adverse affects on fish and wildlife, the entity may commence activity without an agreement. However, if DFG determines that there will be substantial adverse affects, DFG will issue an agreement that includes measures to protect the resource. The entity must conduct the activity in accordance with the agreement. Discussions with DFG staff indicate that section 1602 may be relevant to applications for new diversions as well as previously approved diversions. This could have significant implications for appropriative users with allocations that exceed the entire mainstem flow during the low flow months. If these rights are exercised during the low flow months they could be considered a substantial diversion and curtailed under section 1602.108 Assessment of Compulsory and Regulatory Measures In the course of researching the compulsory and regulatory measures described in this report, Sanctuary Forest was advised by representatives from every agency contacted to pursue voluntary measures. While regulations are in place to protect endangered species and their habitat, enforcement of regulations requires a larger staff than the state of California has been able to support. The failure to develop streamflow protection standards is an important example of inadequate DFG staffing for resource protection. SWRCB directed DFG to identify and list California streams for which minimum flow levels need to be established for fish and wildlife resources by 1984.109 Twenty years later this work has not been done.110 California water law was not written to address the California climate and summer water shortages. SWRCB and DFG staff have described the current system governing water use as incapable of solving current water shortage problems. Historically the state water board has granted water rights without assessing water availability.111 Many rivers in California have been over-appropriated.112 The SWRCB measures that have been developed to address streamflow protection are inadequate and cumbersome. SWRCB staff have commented on the need for a complete revision of California Water Law and more effective coordination between SWRCB, DWR and DFG. Water politics in California are explosive, and changes in water law would likely face a major battle.113 In short, while restrictive and regulatory measures can be considered potential tools for specific applications, they cannot be counted on to solve the Mattole low flow problem. Sanctuary Forest perceives voluntary measures to be the most effective means for improving Mattole streamflows. The proposed streamflow projects in the following section are all voluntary measures. These projects are proposed based on the knowledge gained from the research conducted for this report. Agency and Community Cooperation The agencies that protect fish and wildlife and regulate water use will be most effective if they work in cooperation with the community and local watershed groups. As discussed, voluntary

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measures have the greatest potential for improving Mattole streamflows. If regulatory actions are taken without input from local groups and community support they could backfire, because the new regulations may not fit the specific problems of the Mattole. In addition, independent regulatory action can result in loss of trust and cause the community to be less willing to participate in voluntary solutions. PROPOSED PROJECTS TO IMPROVE MATTOLE STREAMFLOWS The impacts of the low flow problem are of major significance. As discussed earlier in the report, low flows adversely impact all salmonids and threaten the survival of the threatened coho. Because coho have a three-year life cycle, three consecutive acute low flow years could largely extirpate coho populations.114 There may not be time to implement a single project, study the results, and then implement other projects as needed. With this approach, the solutions may be discovered after the Mattole coho are lost. For this reason, Sanctuary Forest proposes several projects to be initiated simultaneously. Funding proposals need to be submitted during the winter and spring of 2004-2005 to facilitate timely implementation of projects. A map showing the location of all proposed projects is in Appendix A-2. Each project will be structured to include a study of benefits to streamflows so that successful projects can be duplicated within the Mattole River Basin as needed. Each project will include the following steps: 1) feasibility study to determine potential benefits and costs; 2) project design and engineering; 3) implementation; 4) monitoring. Sanctuary Forest proposes water conservation and storage projects as well as supplemental water enhancement projects. Community education and outreach will be essential to the success of proposed projects. Hydrology studies are also essential and will provide a basis for site-specific planning of all proposed projects. The proposed projects are described below and organized into two groups: water conservation and storage, and supplemental water projects. These proposals include projects that have been researched and endorsed by Sanctuary Forest and pilot projects for recharge ponds and groundwater pumping that Sanctuary Forest is researching to evaluate potential benefits and risks but does not endorse at this time. Hydrology and education are listed first because they are essential to all proposed projects. Ongoing projects that are already funded or included in a current grant proposal are also listed. Hydrology Assessment Hydrologist Randy Klein performed a preliminary hydrology assessment of the Mattole River low flows in September of 2004 (see Appendix C). This assessment is based on existing data and includes an analysis of possible causes and recommended measures to address the problem. Randy Klein identified many data gaps and recommended an in-depth assessment to study the impacts of water use on flows in the Mattole Headwaters. The analysis of water use in both this report and Randy Klein’s report are based on rough estimates of population and water use. Flow data was also very limited for the Mattole Headwaters. Mattole Headwaters flow analysis is based on one low flow season of measurements at four mainstem sites using the bucket-and-stopwatch method. The USGS stations at Petrolia and Ettersburg provided long-term accurate

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flow data that facilitated analysis of low flows basin wide. The recommended in-depth assessment includes a water use inventory and hydrologic analysis to provide the data needed to accurately quantify the effect of water withdrawals on streamflows.115 The recommended hydrology assessment is necessary for the successful implementation of streamflow improvement measures. The in-depth analysis will provide an accurate assessment of the effectiveness of water conservation measures and indicate the need, if any, for additional flow enhancement measures. The assessment will also provide the documentation needed to enlist community support, fulfill grant requirements, and satisfy documentation requirements for streamflow dedications and water storage of the regulatory agencies. The assessment will be essential for evaluating the need for restrictive measures to protect future river flows, such as county lot size restrictions and fully appropriated river status. The streamflow gauges currently operated by USGS at Petrolia and Ettersburg are instrumental to the continued evaluation of the low flow problem. DWR had planned to shut these gauges down in October of 2004 because of state funding problems. In response to many letters from members of the Mattole River and Range Partnership, the Upper Mattole River and Forest Cooperative, and concerned residents, the gauges will continue operating through the 2004-2005 water season.116 Funding for continued operation of the two gauges needs to be included in the grant proposal for the hydrology assessment described above. Education and Community Outreach Water conservation in the Mattole will only be effective if the majority of landowners participate. As discussed earlier in the report, the scarcity of water as a resource requires a change in how water is perceived and used. This change will occur to the extent that a better understanding of the Mattole and the impacts of human use on streamflows can be conveyed. An education and outreach program is needed that can provide the community with an understanding of water scarcity in the Mattole that is based on scientific observations and assessment of biological and social impacts. Sanctuary Forest proposes an education and outreach program that would enhance the existing Mattole Restoration Council water conservation education program. The program would include three avenues of education. The first is a community conference to present the biological issues of the low flow problems to the community and provide a forum for feedback and questions. The conference would feature a well-known scientist that could present all of the issues clearly and without social judgment. The discussions would focus the community on positive options and help engage important community values. The very successful community conference with research scientist Chris Maser, sponsored by Sanctuary Forest in 1998, is an example of this process. A series of radio broadcasts would be used as a second avenue for outreach. The radio presentations would begin before the conference to help increase interest and attendance. Important outcomes following the conference would be aired for people unable to attend. Regular updates would be scheduled to keep the community aware of streamflow improvement options and the current status of the river.

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The third avenue would consist of small neighborhood stewardship meetings. People who are uncomfortable with big public meetings and who are not reached through the radio could participate in field tours and neighborhood discussions to learn about water conservation measures of interest to them. Water Conservation and Storage Funded Water Storage Families that store water for the dry months in order to enhance streamflows are providing a public benefit at a significant cost and inconvenience to themselves. The current costs for 3.5 months’ storage range from approximately $10,000 to $20,000 per family based on water needs of 25,000 to 65,000 gallons. These costs include the tank and installation but not the plumbing required. Additionally the families need to manage the stored water carefully to ensure that it will last for the dry season. This requires self-monitoring and adjustments in water use. As discussed earlier in this report, beneficial water use is a basic right. Families that refrain from exercising this right during the dry season are giving up the use of a right that can be assigned a monetary value. In many areas with low flow problems, seasonal water rights are leased or purchased. While many families have already installed storage tanks on the Mattole, there are many more who are willing but unable to afford the costs. Also of concern, is the lack of water management agreements with the current owners of large storage tanks. If the tanks are used improperly they can cause considerable damage. For example, if tanks are filled during the dry season, source pools could be pumped dry and lead to fish mortality. Sanctuary Forest proposes a voluntary water storage program whereby landowners would enter into a formal agreement that would restrict all water withdrawals during the dry months (August 1st through November 15th) and be compensated with a storage system that would become their personal property. Ideally, these agreements should be in perpetuity and run with the title of the property. This type of program would require a managing entity to develop, hold and monitor agreements, oversee installation of storage systems, and facilitate the required legal and permitting processes. The proposed funded tank program could begin with 12 landowners in the Mattole Headwaters. The criteria for selection of participating landowners should include consideration of: flow improvement needed for fisheries in the river reach; willingness of landowner to participate in landowner agreement; and financial need of the landowner. The reach upstream of Thompson Creek has been documented to have very low flows and high populations of juvenile salmonids.117 Only seven pumps were observed on the Sanctuary Forest/ Mattole Salmon Group 2004 survey of the Mattole mainstem between Ancestor Creek and Thompson Creek. A storage program for six or seven landowners could replace the need for dry season pumping for this entire mainstem reach of approximately 3 miles. Another mainstem area with observed low flows (flow stopped on September 21st) is the reach between Bridge Creek

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and approximately 0.5 miles upstream of McKee Creek. Pump density was observed to be fairly high with 10 pumps in 1 mile of river. There are already three water storage systems in place and interest is high among the neighboring landowners. Two landowners have already signed DFG landowner agreement forms in the event that tank storage funding can be obtained. If five or six landowners could participate in a water storage program, flows could most likely be improved in this reach. The locations of the two proposed mainstem reaches are shown on the map in Appendix A-2. Landowner Agreements for Streamflow Protection Landowner agreements to reduce seasonal water withdrawals are an important tool for improving flows. On the Mattole, there is not a municipal water agency or water governing entity such as a water master. As discussed earlier, most Mattole residents have riparian rights with no quantifications for water use. Therefore, water is used independently with no coordination or oversight. When water becomes scarce, a more cooperative system is needed. Some communities have opted for adjudication because all water use is then regulated by DWR. As discussed in this report, adjudication is not recommended because it is adversarial, time-consuming and expensive. Sanctuary Forest proposes a community seasonal water management program whereby a managing entity would develop, hold and monitor water use agreements, and facilitate the required legal and permitting processes. The managing entity could also take on the role of a water master to help coordinate water withdrawals if needed. Participation would be voluntary and landowners would be encouraged to enter into perpetual agreements. Seasonal water use rights could be compensated monetarily or with a water storage system if needed. Water use rights could also be dedicated as a donation. Community water management and a landowner agreement program could be developed in phases. The first phase could start with landowner agreements for the 12 landowners who begin the funded tank program. The landowner agreements would be developed to meet the individual requirements of each landowner. The answers to the following four questions largely define the type of agreement needed: 1) What are the specific water conservation measures being considered? 2) Will the water conservation agreement impact the landowner’s water rights? 3) Is there a way to protect the conserved water from other water users in the same reach or downstream? 4) How much water is being conserved? Most of the landowners in the Mattole Headwaters have riparian rights and would be best served by a forbearance agreement or conservation easement. Landowners with appropriative rights or high volume water conservation potential should be considered for 1707 dedications. Water Enhancement Projects to Supplement Flows Recharge Ponds The flow measurements in the Mattole Headwaters conducted by Sanctuary Forest during the late summer and fall of 2004 suggested that recharge ponds could be effective for flow enhancement. This preliminary study did not quantify and compare flows of different tributaries. However, visual observations indicated that Sinkyone/Buck Creek was the only east side tributary with good flow in late August. This creek has two recharge ponds approximately one

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mile upstream of the confluence. During the month of September, Mattole mainstem flows dramatically decreased, dropping by a factor of 30 at the highest flow site and to zero flow at the two downstream locations. Over the same time period, Sinkyone/Buck Creek only decreased by a factor of two and by September 28th had higher flows than all of the measured mainstem sites. Sanctuary Forest proposes further research to evaluate the potential benefits and risks of recharge ponds. Based on the outcome of this research a pilot project would be undertaken. The pilot recharge ponds would be carefully designed with consideration for erosion, fish passage, water quality and non-native species introduction. Inflatable dams would be researched as an alternative to compacted earth. Recommended tributaries for the pilot recharge ponds include Ancestor Creek and McKee Creek. Ancestor Creek restoration site 73 is upstream of all observed anadromy and previous sediment excavation has formed a canyon with good pond potential. Ancestor Creek has low flows and many juvenile salmonids downstream of site 73. Additionally, Ancestor is the main tributary contributing to mainstem flows upstream of Thompson Creek. McKee creek is an east side tributary that had no surface flow near the confluence in late August. None of the east side creeks were flowing well (except Sinkyone/Buck) in late August and most were not flowing at all. A map showing the locations of potential pilot recharge ponds is in Appendix A-2. Brush Clearing and Forest Thinning As discussed in the report, evapotranspiration contributes to water withdrawals and could be a factor contributing to low flows. In other areas, brush and forest thinning has been documented to increase streamflows by reducing evapotranspiration.118 While no studies have been conducted to study the significance of evapotranspiration in the Upper Mattole, the following observations have been made. Anderson Creek has higher night flows than day flows during the summer months. The higher night flows are likely due to lower night water uptake by trees and brush. Mainstem flows just upstream of the Whitethorn junction often improve in early October before the first rain but after the deciduous trees begin showing fall colors. Flow measurements at two mainstem sites increased significantly between September 28th and October 7th. No significant rainfall had occurred and it is hypothesized that reduced evapotransporation as trees became dormant could be responsible. The density of brush and young trees in the Upper Mattole is currently very high due to fire suppression and past logging practices. Sanctuary Forest proposes three brush clearing projects for flow improvement on tributaries. Anderson Creek is recommended because of the day-night observed flow differences. Additionally, Sanctuary Forest and the McMurray family represent most of the ownership along Anderson Creek and could facilitate the implementation and monitoring of the project. Lost River is recommended because it has low flow problems and very dense brush growth in its tributaries. Lost River has juvenile salmonid populations that are currently being impacted by low flows. One representative east side tributary (possibly Stanley or Baker) is also recommended for brush thinning. If the brush thinning improves flows on the representative creek, this enhancement option could be expanded to all similar east side creeks. One forest thinning project is also proposed. Most of the forests in the Mattole Headwaters were heavily logged at one time. Many of these forests were replanted with Douglas fir for timber production. Both the replanted forests and those that were left to come back on their own are

36

growing at a much higher density than the mature forests they have replaced. The riparian area of Lost River Corridor is recommended for forest thinning. The entire 120 acres was heavily logged within the last 25 years and has grown back with dense tan-oak, brush and replanted fir. The riparian area is a high priority for tree thinning, both for potential flow improvement and to restore old-growth characteristics for spotted owl habitat. The locations of the proposed brush thinning projects are shown on the map in Appendix A-2. Groundwater Pumping Groundwater pumping to improve streamflows has been used on the Scott River during times of severe low flows.119 While many dry wells have been drilled in the Mattole, there are also success stories about wells that deliver more than 10 gal/min. Ten gal/min (0.02 cfs) is equal to the measured flow rate of the Mattole mainstem on September 11, 2004 at site MS2 (Stanley Creek/Mattole confluence). This site had the highest flow rate of the four sites measured in the mainstem upstream of Bridge Creek. According to these calculations, one well could provide more flow than was observed in the Mattole Headwaters, upstream of Bridge Creek, from September 11th to October 8th. Solar powered pumps and solar panels can be installed to provide continuous pumping during the day. Sanctuary Forest proposes further research to evaluate the potential benefits and risks of groundwater pumping to improve streamflows. Based on the outcome of this research a pilot well would be undertaken. Preliminary studies would include evaluation of water quality and temperature from local wells and assessment of impacts to Mattole River water quality. Site evaluation would include investigation of the potential presence of chemical contaminants. Additionally, the impacts of groundwater pumping on the surrounding aquifers need to be evaluated. The pilot well location is proposed along one of the east side tributaries to the Mattole. Vanauken Creek is a likely candidate because it has the potential to provide good juvenile samonid habitat if the flows were improved. The potential location for a pilot well along Vanauken Creek is shown on the map in Appendix A-2. Ongoing Projects to Improve Mattole Streamflows Water Conservation and Storage Mattole Restoration Council Education, Outreach and Water Conservation Tune-ups Since the spring of 2003, the Mattole Restoration Council has developed an outreach and education program to teach landowners about water storage options and conservation techniques for homes and gardens. Free water conservation services are available to evaluate Mattole residential water systems and make recommendations for water conservation. These services include evaluations of the entire system from the source and tank filling system to garden and household use. Mattole Restoration Council also offers free low-flow shower heads, faucet aerators and mechanical tank valves on a cost-share basis. Pioneer Tank Installations Private landowners have led the way in water storage. Approximately 18 Pioneer tanks, storing volumes of 20,000 to 65,000 gallons each, have been installed in the Mattole in the last year and a half. Whitethorn Construction and California State Parks have also participated. Whitethorn

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Construction expanded its 32,000 gallon tank farm that utilizes rainwater collection with a 52,000 gallon Pioneer tank. The State Park Nursery at Shadowbrook installed a 65,000 gallon Pioneer tank this spring. Eighteen additional Pioneer tanks have been installed by Whitethorn Construction in other watersheds of Humboldt County. Humboldt County is the biggest purchaser of Pioneer Tanks in the USA.120 Whitethorn Construction has a long history of service to the Upper Mattole community and has been instrumental to the widespread installation of Pioneer tanks. In the past year, Whitethorn Construction has become authorized for sales and installations of Pioneer tanks in Humboldt County. Whitethorn Construction is also working on improvements in tank design, including leak safety plumbing and rainwater collection. 121 Pilot Project ─ Water Conservation Easement The following project illustrates the use of a water conservation easement to protect streamflows on a site-specific basis. Sanctuary Forest is developing a conservation easement with the landowners to protect the habitat values of their 22-acre property. The property stewardship objectives are focused on improving and restoring fish habitat in both Anderson Creek and the Mattole River. The proposed structure for protection of streamflows is a forbearance agreement that would be incorporated into the terms of the conservation easement. Sanctuary Forest does not recommend a 1707 dedication because the landowner does not have appropriative rights. A 1707 dedication would be needed if the landowner had appropriative rights and was at risk of losing rights by non-use. This landowner has riparian rights, which are not put at risk through non-use. The forbearance agreement will not legally protect the conserved water from downstream users. While a 1707 dedication would provide legal protection of conserved water from appropriative rights holders, it would not protect the water from riparian rights holders. The predominance of downstream water users have riparian rights, rendering a 1707 dedication ineffective for protection of conserved water in this location. The primary objective of the water conservation easement is to restrict water withdrawals from Ancestor Creek and the Mattole River during the low flow months. The easement will refer to a water management plan wherein specific guidelines for low flow season water management will be defined. The water management plan will define a grace period during which steps toward full compliance with easement restrictions will take place. The grace period will allow time for needed water efficiency and storage improvements. The specific objectives and timeline will be developed with the landowner. Funding to assist with water efficiency and storage will be pursued by Sanctuary Forest. The management plan will also include emergency provisions, water system maintenance guidelines, and a monitoring program. The monitoring program will likely include a water meter to be managed by the landowner. The frequency of monitoring is planned for two visits per year: spring monitoring to ensure that water system maintenance and water conservation systems are in place for the low flow months, and fall monitoring to review water meter records and determine if the objectives are being met. The

38

monitoring will provide feedback on the success of the water management plan and indicate the need for additional water conservation measures and/or restriction modifications. The landowners use the property as a vacation home and part-time residence. It is not anticipated that the property will become a full-time residence. The household water use is low because of the part-time use. The gardens and orchards are small and do not have significant water requirements. A pond is maintained for fire safety and recreational use. The pond is listed with the CDF for use by helicopter access. The pond currently leaks badly and requires a significant volume of water to be pumped from the creek each day to keep it full. The landowners intend to repair the pond, which should significantly reduce the volume of water pumped into the pond. However, there will still be evaporative losses. The estimated daily water use on the above-mentioned property during the last 5 years is calculated below. Calculations are based on the number of people in the household, the square footage of gardens and orchard, and the pumping time required to keep the pond full. SWRCB standard household (75gpd/person) and irrigation (18.5 gpd per 100 sq ft) daily volumes were used. • Household: 3 people at half-time use = 112 gpd • Garden & Orchard: 1000 sq ft = 185 gpd • Pond: 6 hours/day x 60 min/hr x 3.5 gal/min = 1,260 gpd • Total daily water use = 1557 gallons The estimated amount of water that could be conserved is based on repairing pond leaks and is estimated at 1000 gpd. The total daily water use of 300 gpd for the household, garden and orchard is very moderate. Water Enhancement Projects to Supplement Flows Sediment Removal In 2003 Sanctuary Forest completed a large sediment removal project in the Upper Mattole Headwaters to address potential sediment delivery volumes of 50,000 cubic yards. Many of the tributaries that had been buried under logging roads began flowing when excavated. The Mattole River and Range Partnership is currently planning a restoration project for 2005 and 2006 to complete treatment of sediment sources on the UMRFC lands and on the lands of private and industrial timber landowners in the Upper Mattole. This sediment removal work will reduce sediment in the treated tributaries and reduce potential downstream sedimentation. The sediment removal work will also help restore flows in buried tributaries. In the absence of heavy sediment loads delivered from the tributaries, the natural balance of sedimentation and scour can be restored, historic pools now filled with sediment may form again and provide important habitat. Fish Habitat Structures The Mattole River and Range Partnership is also planning to build more fish habitat structures. In addition to providing important habitat for fish, these structures facilitate scour and pool formation. Many pools were observed at fish habitat structure sites on the Mattole Headwaters survey in August of 2004. These pools were formed or enhanced by the fish habitat structures.

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As mentioned above, many historic Mattole pools have been filled with sediment resulting in less water and less habitat. The pools are particularly important for providing habitat in low flow years when the shallow reaches dry up or flow subsurface.

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References and Literature Cited

1 Montaigne, F., “Water Pressure,” National Geographic, Vol. 202, No. 3, September 2002, pp. 2-32. 2 Pimm, Stuart L., The World According to Pimm. McGraw-Hill, 2001, pp. 111-112. 3 Holland, E., The State of California Rivers. Trust for Public Lands, 2001, p. 9. 4 Sommarstrom, S., Scott River Water Trust Project, personal communication, 2004. 5 Downie, Scott T., C. W. Daveport, E. Dudik, F. Yee, and J. Clements (multi-disciplinary team leads), Mattole River Watershed Assessment Report (“NCWAP Report”). North Coast Watershed Assessment Program, California Resources Agency and California Environmental Protection Agency, Sacramento, California, 2002, p. 2. 6 Mattole Restoration Council, Dynamics of Recovery, 1995, pp. 4-19. 7 Downie et al., NCWAP Report, p. 4. 8 Mattole Restoration Council, Dynamics of Recovery, 1995, pp. 2-9. 9 Lingel, R., Mattole Salmon Group, pers. comm., July 2004. 10 Ibid. 11 Brown, M., Mattole Salmon Group, pers. comm., 2004. 12 Downie, S., California Department of Fish and Game, pers. comm., 2004. 13 Downie, Scott T., C. W. Daveport, E. Dudik, F. Yee, and J. Clements (multi-disciplinary team leads), Mattole River Watershed Assessment Report (“NCWAP Report”). North Coast Watershed Assessment Program, California Resources Agency and California Environmental Protection Agency, Sacramento, California, 2002. 14 Department of Fish and Game, Recovery Strategy for California Coho Salmon, Sacramento, California, 2004. 15 Downie, et al., NCWAP Report, Appendix C: Hydrology. 16 U.S. Geological Survey Water Resources. Petrolia Discharge, water years 2000-2003. Ettersburg Discharge, water years 2000-2003. 17 Klein, R. D., Preliminary Hydrologic Assessment of Low Flows in the Mattole River Basin. Sanctuary Forest, Mattole Salmon Group and Mattole Restoration Council, 2004, pp. 8-9, 18. 18 Klein, R. D., Preliminary Hydrologic Assessment of Low Flows in the Mattole River Basin. 2004, p.8, figure 1. 19 Klein, R. D., Preliminary Hydrologic Assessment of Low Flows in the Mattole River Basin. 2004, p.9. 20 U.S. Geological Survey Water Resources. Petrolia Discharge, water years 2000-2003. 21 Susich, G. ,USGS, pers. comm., 2004. 22Klein, R. D., Preliminary Hydrologic Assessment of Low Flows in the Mattole River Basin, pp.16-17. 23 Susich, G. ,USGS, pers. comm., 2004. 24 Orcutt, K., pers. comm., 2004. 25 Brown, M., Mattole Salmon Group, pers. comm., 2004. 26 Brown, M. and Wheeler D., Mattole River Dissolved Oxygen Monitoring, 2003 Field Season. Mattole Salmon Group, 2004. 27 California Department of Fish and Game, “Mattole River Water Diversions” (map), 2004. 28 Witts, K., California Department of Fish and Game, pers. comm., 2004. 29 Downie, et al., NCWAP Report, Appendix C: Hydrology. 30 Susich, G. ,USGS, pers. comm., 2004. 31 Klein, R. D. Preliminary Hydrologic Assessment of Low Flows in the Mattole River Basin. 32 Mattole Restoration Council, Dynamics of Recovery, 1995, pp. 4-19. 33 Klein, R. D., p. 4. 34 Downie, et al., NCWAP Report, Appendix C: Hydrology, p. 23. 35 “Whitethorn Community Takes Action to Keep the River Flowing,” Mattole Restoration Council newsletter, issue 20, Summer/Fall 2003. 36 Cook, J., Whitethorn Construction, pers. comm., Oct 2004. 37 State Water Resources Control Board, How to File an Application to Appropriate Water in California, 2000, Appendix. 38 Ibid. 39 Cook, J., pers. comm., 2003. 40 “Whitethorn Community Takes Action to Keep the River Flowing,” Mattole Restoration Council newsletter, issue 20, Summer/Fall 2003. 41 Lamborn, J., pers. comm., 2004. 42 Downie et al., NCWAP Report, Appendix C: Hydrology, pp. 24-25. 43 State Water Resources Control Board, A Guide to California Water Rights Appropriations, 2001.

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44 Ibid. 45 Vorpagel, J., California Department of Fish and Game, pers. comm., 2004. 46 Mooney, D. B. and M. A. Burch, Water Acquisition Handbook: A Guide for Acquiring Water for the Environment of California. Trust for Public Lands, 2003, p. 113. 47 Ellison, Schneider & Harris, L.L.P., Assessment of Scott River Options. Siskiyou Resource Conservation District and the Scott River Watershed Council, 2004. 48 Donlan, R., attorney with Ellison, Schneider & Harris, L.L.P., pers. comm., 2004. 49 Mooney et al. 50 Donlan, R., pers. comm., 2004. 51 Donlan, R., pers. comm., 2004. 52 Mooney et al. 53 Donlan, R., pers. comm., 2004. 54 Ibid. 55 Morwaka, K., State Water Resources Control Board, pers. comm., 2004. 56 Mooney et al. 57 Ellison, Schneider & Harris, L.L.P. 58 Donlan, R., pers. comm., 2004. 59 Mooney et al. 60 Morwaka, K., pers. comm., 2004. 61 Donlan, R., pers. comm., 2004. 62 Morwaka, K., pers. comm., 2004. 63 Ibid. 64 Mooney et al. 65 Ibid. 66 Ibid. 67 Ibid. 68 Rich, C., State Water Resources Control Board, pers. comm., 2004. 69 Vorpagel, J., pers. comm.,2004. 70 Marony, P., State Water Resources Control Board, pers. comm., 2004. 71 Ibid. 72 Vorpagel, J., pers. comm.,2004. 73 Marony, P., State Water Resources Control Board, pers. comm., 2004. 74 Hart, D., Humboldt County Tax Assessor, pers. comm., 2004. 75 Larson, D., Mendocino County Tax Assessor, pers. comm., 2004. 76 Hart, D., Humboldt County Tax Assessor, pers. comm., 2004. 77 Ibid. 78 Ibid. 79 Monschke, Jack, watershed restorationist, pers. comm., 2004. 80 Clements, J., California Department of Water Resources, pers. comm., 2004. 81 Hedt, T., Natural Resources Conservation Services, pers. comm., 2004. 82 Partners for Fish and Wildlife Program, application packet, 2003. 83 Flosi, G., California Department of Fish and Game, pers. comm., 2004. 84 Department of Water Resources and State Water Resources Control Board, Integrated Regional Water Management Program – Proposition 50, 2004, Chapter 8. 85 California Association of Resource Conservation Districts, http://www.carcd.org, accessed in 2004. 86 Sommarstrom, S., pers. comm., 2004. 87 Pierson, G., California Department of Water Resources, pers. comm., 2004. 88 Humboldt County Resource Conservation District, brochure, 2004. 89 Hedt, T., NRCS, pers. comm., 2004. 90 Montaigne, F., “Water Pressure,” National Geographic, Vol. 202, No. 3, September 2002, pp. 2-32. 91 Sommarstrom, S., pers. comm., 2004. 92 Marony, P., State Water Resources Control Board, pers. comm., 2004. 93 Rich, C., State Water Resources Control Board, pers. comm., 2004. 94 State Water Resources Control Board, A Guide to California Water Rights Appropriations, 2001. 95 Marony, P., State Water Resources Control Board, pers. comm., 2004.

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96 Donlan, R., pers. comm., 2004. 97 Clements, J., California Department of Water Resources, pers. comm., 2004. 98 Mooney et al. 99 Sommarstrom, S., pers. comm., 2004. 100 Donlan, R., pers. comm., 2004. 101 Ibid. 102 Vorpagel, J., pers. comm., 2004 103 Sommarstrom, S., pers. comm., 2004 104 Spencer, M., Community Development Services, Humboldt County, pers. comm., 2004. 105 Girard, K., Planning Department, Humboldt County, pers. comm., 2004. 106 California Endangered Species Act (Fish & Game Code sec. 2050 et seq.). 107 Martz, C., California Department of Fish and Game, pers. comm., 2004. 108 Ibid. 109 State Water Resources Control Board, Statutory Water Rights Law, Public Resources Code, Division 10, 2004. 110 Martz, C., California Department of Fish and Game, pers. comm., 2004. 111 Rich, C., State Water Resources Control Board, pers. comm., 2004. 112 Vorpagel, J., pers. comm., 2004. 113 Rich, C., State Water Resources Control Board, pers. comm., 2004. 114 Lingel, R., pers. comm., 2004. 115 Klein, R. D., pp. 19-22. 116 Senter E., Department of Water Resources, pers. comm., 2004. 117 Lingel, R., pers. comm., 2004. 118 Pierson, G. , Department of Water Resources, pers. comm., 2004. 119 Clements, J., California Department of Water Resources, pers. comm., 2004. 120 Cook, J., pers. comm., 2004. 121 McKee, R., Whitethorn Construction, pers. comm., 2004.

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Appendix A: Sanctuary Forest River Monitoring and Project Maps

Appendix A-1: Site Map for River Flow Measurements (2004)

Appendix A-2: Site Map for Proposed Projects

Appendix B: Department of Fish and Game Map, “Mattole River Water Diversions”

Appendix C: “Preliminary Hydrologic Assessment of Low Flows

in the Mattole River Basin,” Randy Klein, September 2004

PRELIMINARY HYDROLOGIC ASSESSMENT OF LOW FLOWS IN THE MATTOLE RIVER BASIN

Prepared for:

Sanctuary Forest, Inc.

And Mattole Restoration Council

By:

Randy D. Klein

Hydrologist

September, 2004

Mattole Low Flow Hydrology, R. Klein, Sept., 2004

TABLE OF CONTENTS Introduction..................................................................................................................................... 2 Human-induced Causes of Low streamflow................................................................................... 2

Water withdrawals .................................................................................................................................... 3 Changes in runoff properties of hillslopes ................................................................................................ 3 Changes in streambed hydraulic properties due to aggradation................................................................ 4

Existing Data and Previous Studies ................................................................................................ 4 Climatic and Hydrologic Data .................................................................................................................. 4 Water Use.................................................................................................................................................. 4 Upper Mattole ........................................................................................................................................... 6

Rainfall and Low Flow Hydrologic Analyses ................................................................................ 7 Northcoast Watershed Assessment Report ............................................................................................... 7 Further Analyses of Low Flows................................................................................................................ 9 Low flow measurements during late summer and early fall, 2004 ......................................................... 16

Preliminary Conclusions and Recommendations ......................................................................... 18 Reducing Dry Season Demand ............................................................................................................... 18 Watershed Restoration and Recovery ..................................................................................................... 19 In-depth Assessment ............................................................................................................................... 19

Literature Cited ............................................................................................................................. 21 Appendix A: Study Proposal Time Estimates for Mattole River Low Flows .............................. 22

LIST OF FIGURES

Figure 1. Mattole River near Petrolia and Ettersburg 7-day minimum low flows ……………………… ..8 Figure 2. Mean monthly discharge during dry months for Petrolia, 1965-2004…………………………...9 Figure 3. Departures from 1965-2004 mean monthly low flow discharges for Petrolia………………….10 Figure 4. Antecedent rainfall and 7-day minimum low flow for Petrolia…………………………………11 Figure 5. Antecedent rainfall and July discharge for Petrolia, 1966-2003………………………………..12 Figure 6. Antecedent rainfall and August discharge for Petrolia, 1966-2003……………..…………….. 12 Figure 7. Antecedent rainfall and September discharge for Petrolia, 1966-2003…………………….…...13 Figure 8. Antecedent rainfall and October discharge for Petrolia, 1966-2003……………………….….. 13 Figure 9. Rainfall, API, and discharge for Petrolia, 2001-2004……………………..…………………....15 Figure 10. Actual and estimated unimpaired flows and water withdrawals for Petrolia, 2001-04………. 15 Figure 11. Low flows at five sites in the Upper Mattole River, 2004…………………………….………17 Figure 12. Late summer flow recession on the main stem Upper Mattole River, 2004…...……...………17

LIST OF TABLES Table 1. Estimated dry season water use for the Mattole River basin…………………………………….. 6 Table 2. Estimated dry season water use for the Mattole River southern sub-basin……………………… 7 Table 3. Coefficients of determination for regression of antecedent rainfall on discharge, 1966-2003…. 14

Mattole Low Flow Hydrology, R. Klein, 2004 1

INTRODUCTION Among the suite of habitat conditions constraining salmonid run strength (i.e., limiting factors) in the Mattole River basin, low summer and early fall streamflows have been identified as important. Some people familiar with the history and fisheries of the Mattole River now consider the low flow issue to be of greater importance than erosion and sedimentation from past and ongoing land use. In recent years, juvenile salmonids have become stranded in pools due to excessively low flows, causing mortality and necessitating fish rescue operations. In particular, the summer of 2002 was the driest in the 55-year record of flows on the Mattole River near Petrolia, and the current conditions (summer, 2004) may well prove to be drier still. A variety of factors influence low flows, such as, climate (rainfall, temperature, relative humidity, wind speed), vegetation species and maturity, ground disturbance, streambed sedimentation, and water use for domestic and agricultural purposes. Of these, only vegetation, ground disturbance and water use are subject to human influences and therefore might be modified to minimize effects on low flows. But the relationships between low flows and influential factors are complex, especially in a basin as large and diverse as the Mattole River, and reducing human water use is often a difficult, expensive, painful undertaking, requiring both technological as well as lifestyle changes. Therefore, water management and conservation efforts in the Mattole River basin must be based on a thorough, quantitative, site-specific understanding of hydrologic processes. This report presents a preliminary analysis of low flows in the Mattole River basin with the following objectives: 1) to make an initial assessment of the possible effects of water withdrawals on low flows; and 2) to describe a detailed investigation that could be undertaken to determine the magnitude and most important locations of water withdrawal impacts on low flows and recommend remedies. HUMAN-INDUCED CAUSES OF LOW STREAMFLOW Although climate exerts the dominant control on stream discharge, three categories of the effects of human activities on low flows in the Mattole River are listed and discussed below. 1) Water withdrawals for:

a) domestic use, b) irrigation of pastures and stock watering, c) irrigation of gardens, orchards, and truck farms, d) fire suppression, e) dust control and perhaps others.

2) Changes in runoff properties of hillslopes:

a) reduced interception losses from timber harvest, b) reduced evapotranspiration from timber harvest, c) reduced infiltration capacity from soil compaction due to tractor yarding and road construction.

3) Changes in streambed hydraulic properties due to aggradation:

a) lower proportion of surface to subsurface flow, b) changing a stream segment from a ‘gaining’ reach to ‘losing’ reach. c) Higher width to depth ratios increasing vulnerability to warming and evaporation.

Mattole Low Flow Hydrology, R. Klein, 2004 2

Water withdrawals Obviously, withdrawal of surface water directly from a flowing stream will reduce streamflow. The significance of direct withdrawals depends on the rate of streamflow compared with the rate of withdrawal. A single, relatively large withdrawal, or several smaller withdrawals, within a small stream can have a large effect locally. Effects are most acute when streamflows are lowest, as these are times when supply is low and demand (for most uses) is high. However, not all withdrawals are alike. Withdrawal from groundwater wells will have a delayed effect, if any, on streamflow, depending on the proximity to the stream, the source(s) of groundwater recharge, the pumping rate, and the permeability of the supply aquifer. A well located high up in the watershed, even if near a small stream, will have a much delayed and attenuated effect on the mainstem. Not all water withdrawn from the natural hydrologic system is lost to the surface flow network. For example, a portion of the water used to irrigate a terrace pasture located in the valley adjacent to the stream may flow back towards the river as groundwater, a term called ‘irrigation return flow’. Similarly, a portion of the water from a leaking or overflowing water storage tank may, in some instances, find its way back to the creek via surface or subsurface pathways, although evaporation may claim a significant portion. Effects of water withdrawals are complex, particularly in a hydrologically-complex area such as the northcoast. However, a good inventory of withdrawals, including location, rates and timing of withdrawals, will provide a basis, along with other information, for examining the significance of water withdrawals on streamflow and prioritizing actions to reduce harmful effects on the stream ecosystem. Later in this report, rough estimates of water withdrawals are compiled from several sources and compared with stream discharge in a crude, first-cut water balance.

Changes in runoff properties of hillslopes Human activities can have profound effects on rainfall-runoff relationships, and this has been the subject of much work in the hydrologic research and engineering fields. Urbanization creates impervious or less pervious ground (e.g., roofs, parking lots, streets) than vegetated surfaces, and nearly all the rain falling on such surfaces immediately runs off as stormflow, rather than infiltrating and recharging aquifers. While paving is not an issue in the Mattole River, other, less dramatic effects of land use have undoubtedly played a role in altering the hydrology of the basin. Research has shown that timber harvesting can increase minimum summer and fall low flows in north coastal streams. For example, Keppeler (1998) showed that low flows increased by as much as 148% in the North Fork Caspar Creek research watershed following clearcutting 50% of the watershed. The increases were attributed to reduced interception (rainfall caught in the tree canopy and evaporating before falling to the ground) and reduced evapotranspiration losses following canopy removal. While minimum low flows were enhanced by experimental logging in Caspar Creek, this case is somewhat different than logging styles in the Mattole. Specifically, tractor yarding, which compacts the soil and removes the protective duff layer, thereby reducing rainfall infiltration, was kept to a minimum in Caspar Creek. In contrast, tractor yarding in the Mattole was widespread, and continues today, although at a much reduced rate compared to the logging boom of the 1950s through 1970s. Compaction and duff removal would tend to negate some of the low flow enhancement derived from canopy removal by reducing infiltration. Further, increases in summer low flow that might have been derived from earlier logging have likely waned due to vegetation recovery, although the effects of soil compaction and duff removal are likely to take longer because of the legacy of haul roads (estimated at over 3,000 miles) and skid trails that remain on vast areas within the Mattole River basin.

Mattole Low Flow Hydrology, R. Klein, 2004 3

Changes in streambed hydraulic properties due to aggradation It is well-established that massive erosion in the Mattole River basin, caused by both natural and human factors, resulted in massive aggradation of lower-gradient streambeds, some of which remain buried under feet or tens of feet of gravel. Madej and Ozaki (1996) have shown that aggraded sediment can take decades or longer to be flushed from a river reach, depending on the magnitude of storms and continued upstream sediment supply and channel transport efficiency. Stream discharge commonly consists of both surface and subsurface flow, except in bedrock streams where virtually all flow is at the surface. Where streambed sedimentation is severe, a greater proportion of the water supplied from upstream flows subsurface through the relatively permeable streambed, leaving less at the surface to provide habitat for many aquatic species. This can be readily seen where a log jam elevates the streambed through localized aggradation. Upstream of the aggraded reach above the log jam, flow can be significantly greater than in the aggraded reach just upstream of the log jam, and it is not uncommon for all flow to go subsurface near the log jam under low flow conditions. The same phenomenon occurs, to varying degrees, where channels have become aggraded, without the influence of a log jam, over great lengths due to excessive coarse sediment loads. A second distinct, but overlapping, effect of aggradation is to elevate the water surface within the channel at both high and low flows. This can have a negative impact during low summer flows by reversing the by groundwater gradient from one that slopes (and flows) toward the channel to one that slopes away from the channel. Whereas before aggradation, groundwater may have contributed to streamflow (termed a ‘gaining reach’), surface water may flow from the channel into the adjacent aquifer following aggradation (termed a ‘losing reach’), causing an otherwise perennial stream to become intermittent. Another possible effect of aggradation stems from channels becoming wider and shallower, which exposes a larger surface area to warming from direct sunlight or from contact with the air above the water surface. The combined effects of lower surface flow rates and greater width to depth ratios are likely to be causing substantial warming and consequently greater evaporation in some stream reaches of the Mattole watershed. EXISTING DATA AND PREVIOUS STUDIES

Climatic and Hydrologic Data Rather than list all historic and contemporary sources of climatic and hydrologic data collected in the Mattole River basin, the reader is referred to the Northcoast Watershed Assessment Program’s (NCWAP) Mattole River report (NCWAP, 2001). Appendix C of this report, prepared by the California Department of Water Resources (DWR) lists all known official (government sponsored) data collection efforts in the Mattole and has assembled relevant data and performed some basic analyses, primarily of rainfall and streamflow. In addition to official data collection, numerous basin residents keep records of such basic information as temperature and rainfall. Most relevant to this report are rainfall and streamflow records. The rainfall and streamflow frequency analyses in the NCWAP report are not repeated here, although it would be useful to update them with more recent (2001-04) data. Instead, I used them as presented and considered more recent data in the context of the existing analyses.

Water Use The NCWAP study provides a listing of appropriative water rights granted within the Mattole River basin (appropriative water rights are rights to withdraw surface water from a stream located off the property of the appropriator and an application must be made to the State for such a right, whereas riparian water rights are rights to surface water withdrawal from a stream reach passing through or adjacent to the withdrawer’s property and need not be applied for or registered with the State). Fifty water rights are

Mattole Low Flow Hydrology, R. Klein, 2004 4

listed in the NCWAP report and the sum of maximum diversion rates for 47 of these (no data exist for three) is 3,021,730 gallons per day (gpd), which equates to 4.68 cubic feet per second (cfs). These diversions are scattered throughout the basin, with 20 withdrawing water from the main stem Mattole and the remainder from tributaries. The dominant use reported for these withdrawals is for irrigation, with domestic use, fire protection, and stock watering also common. The NCWAP report acknowledges that there are likely many more water withdrawals within the Mattole than those reported, both in terms of riparian as well as pre-1914 appropriative rights. Interestingly, a single water right exists for fish and wildlife protection within the Mattole River basin; a 0.1 acre-feet annual volume right owned by the US Bureau of Land Management on an unnamed spring. Periodic reporting of use is required of water right grantees, that is, they must file a report with the State that documents their use of the water in amounts consistent with the right (however, there is no penalty for non-reporting). A water right can be forfeited after five years of non-use, assuming someone is looking. Consequently, given the high potential value of a water right, it is reasonable to assume that most irrigation water rights are exercised, if for no other reason than to avoid forfeiture, and the actual withdrawals are commensurate with the respective rights. If the Mattole River basin is typical of other areas of California, unreported riparian water withdrawals are numerous and there are likely many more appropriative withdrawals than listed in the records. It should be noted that some proportion of irrigation water applied in some situations can flow back to the river as groundwater, a process termed ‘irrigation return flows’. This would typically be expected to occur at irrigated terraces adjacent to a tributary stream or the Mattole main stem. Where this occurs, the net loss to the surface water flow regime is less than the diversion rate by the amount not lost to evapotranspiration or held in plant matter. Water use for the Mattole River basin was also estimated in the NCWAP report. Acreages of irrigated lands, by general type of agricultural use, are periodically determined by the DWR from aerial photos (scale 1:24,000). A survey conducted in 1996 estimated 896 acre-feet for the irrigation season (taken as June through October here, or a five-month period), equivalent to about 1,946,300 gpd (3.01 cfs) average withdrawal for the year, was used to irrigate about 604 acres that year (584 acres of pasture, 14 acres of almond orchards, and 6 acres of truck farm). In addition, a per-capita approach (assuming about 85 gpd per person) was used to estimate domestic water use for the estimated 405 households (1,132 people) in the basin. The estimated domestic water use amounts to about 0.153 cfs. However, neither of the above figures includes irrigation of small-scale domestic gardens. Summing the estimated domestic and agricultural water usage from the NCWAP report yields about 1.38 cfs, or only about 30% of the summed water rights for the basin. As mentioned earlier, the summed water rights likely represent only a fraction of total water use in the basin. Thus, there is likely a lot more water use occurring than the NCWAP estimates would represent. The NCWAP (2000) report estimates there are 405 households in the Mattole River basin. Daily per-household use during the summer months is estimated at about 900 gpd (T. McKee, pers. comm., 2004) based on knowledge of local lifestyles (this assumes 75 gpd per person for personal use at 3 persons per household, 475 gpd for lawns and gardens, and about 200 gpd lost due to plumbing leaks and storage tank overflow). Thus, a very approximate locally-derived estimate of domestic use totals 364,500 gpd (or 0.56 cfs), about four times higher than that given in the NCWAP (2000) report (0.153 cfs). For lack of more recent or locally-derived information, basin-wide irrigation use from the NCWAP (2000) report is the best information available. As mentioned above, a 1996 air photo-based inventory estimated large-scale (non-domestic) irrigation use at 896 acre-feet, translating to about 3.01 cfs for the June-Oct (five-month) irrigation season. Small-scale (non-domestic) agricultural irrigation is estimated at 0.16cfs. This category includes all other small commercial gardens such as farmer’s market gardens and orchards.

Mattole Low Flow Hydrology, R. Klein, 2004 5

Another as yet unquantified but potentially significant use of water in the Mattole River basin is watering of non-surfaced roads for dust abatement. This is commonly done during the dry season on non-surfaced logging haul roads being used for current operations. Water application is the most common means of controlling dust because it is cheaper than the alternatives of applying dust palliatives or surfacing roads with rock or blacktop. Data exist in the records of timber harvest activities maintained by the California Department of Forestry and Fire Protection (CDF) that could be used to estimate water volumes used for dust abatement, but this was beyond the scope of this analysis. Table 1 lists the available estimates, considered to be the best currently available, of water use during the summer and early fall (months of low flows) in the Mattole River. As indicated, irrigation is the dominant use in terms of volume, composing about 85% of total withdrawals. In addition, estimated water use is about 80% of the sum of water rights provided above, so either the estimates are low or water rights are not fully exercised.

Table 1. Estimated dry season water use for the Mattole River basin.

Use Type Rate (gpd) Rate (cfs) Large and small scale irrigation 2,048,826 3.17 Domestic: personal 91,125 0.14 Domestic: gardens and lawns 192,375 0.30 Domestic: waste (leaks and overflows) 81,000 0.13 Total = 2,413,326 3.74

Domestic use of water has undoubtedly grown over the years, both because of population growth and increases in per-capita consumption. The NCWAP reports that there are presently 405 households in the Mattole River basin based on census data compiled in 2000. Local knowledge can shed some light on actual water use trends within the Mattole River. Ms. Tasha McKee, a lifelong resident of the Mattole, reports:

“Water use per person has increased significantly in the past 40 years with changes in lifestyle. In Whitethorn during the 1950’s and 1960’s most families depended on gravity flow water from springs and small creeks. These water sources were very limited and households were managed with very little water. My family used a spring that would often dry up in late summer. We used an outhouse in the summer and a ringer washer that could do 10 loads of wash with the same water. The bathwater was shared and reused by all 6 kids. Our garden was small and in dry years we quit watering in late summer. I don’t remember knowing anybody that had a lawn in the Whitethorn area. The only irrigated fields were at a sheep ranch in Ettersberg. Even the orchards were unirrigated in those days. Since the 1970’s, most of the families in the Whitethorn [area] are able to afford pumps to supplement their water use and withdraw water from nearby creeks or the river. Modern lifestyles most often include indoor plumbing and automatic washing machines and dishwashers that are not water efficient. Many families enjoy gardening and landscaping and some maintain lawns. Most of the orchards are also irrigated.” [‘Options and Obstacles to Voluntary Water Conservation’, Sanctuary Forest Incorporated, 2004]

Upper Mattole Of particular interest is water use and low flow effects within the southern sub-basin of the Mattole River, defined in the NCWAP (2000) assessment as the uppermost 27 square miles of the watershed. About one-quarter (or 100) of the total households in the Mattole River (405) are located here, and only a few small

Mattole Low Flow Hydrology, R. Klein, 2004 6

farms. The southern sub-basin includes Calwater Bridge Creek and Thompson Creek planning watersheds and the following major tributaries: 1) the upper Mattole River, 2) Thompson Creek, 3)Baker Creek, 4) Mill Creek, 5) Anderson Creek, 6) Bridge Creek, and 7) Vanauken Creek. There are also a number of other named tributaries within the southern sub-basin. Table 2 lists water use for the southern sub-basin based on estimates from local knowledge (T. McKee, pers. comm., 2004). Several species of salmonids (Chinook and coho salmon and steelhead trout) are know to use several streams in the area, based on fish surveys conducted by various groups. Juveniles depend on habitat within the southern sub-basin during the driest parts of the year. However, some of the reaches uses by juveniles have gone dry in recent years (including the current year), thus summer flow conditions are a critical concern, and determining if or how the problem can be addressed through management is a high priority.

Table 2. Estimated dry season water use for the Mattole River southern sub-basin.

Use Type Rate (gpd) Rate (cfs) Large and small scale irrigation 25,000 0.039 Domestic: personal 22,500 0.035 Domestic: gardens and lawns 47,500 0.073 Domestic: waste (leaks and overflows) 20,000 0.031 Businesses, schools, and other organizations 15,000 0.023 Total = 130,000 0.201

As indicated, domestic water use in the southern sub-basin is proportional to that in Table 1 for the entire watershed, owing to use of the same per-household rates. However, agricultural use (ranching and farming ) is far lower on a per-unit-area basis (drainage areas for the southern sub-basin and entire Mattole are 26 mi2 and 296 mi2, respectively). The total estimated use per square mile in the southern sub-basin amounts to only about 4,900 gpd (0.0076 cfs) per square mile, or about 40% lower than that for the entire Mattole River (8,200 gpd (0.0126 cfs) per square mile), despite the additional use estimate for businesses, etc., in the southern sub-basin. To compare the estimated water use with low flows in for the Upper Mattole, it is necessary to use the flows measured at the USGS Ettersburg gage. This requires increasing water use estimated for the southern sub-basin (27 mi2) to account for the greater watershed area above Ettersburg (58.1 mi2). For lack of a better method, water use in the southern sub-basin (0.201 cfs, Table 2) was multiplied by the drainage area ratio (58.1/27 = 2.15) resulting in an estimated water use of about 0.43 cfs for the area above Ettersburg. This amounts to about 9% of the 7-day minimum low flow (4.80 cfs) for the dry summer of 2001, and about 11% of that in 2002, an extremely dry summer. These represent much smaller percentages than at the Petrolia gaging station, where estimated water use was 22% and 28% for 2001 and 2002, respectively. While these estimates suggest that water use is a relatively smaller percentage of low flow in the Upper Mattole, it may be more significant within specific areas, as discussed later. RAINFALL AND LOW FLOW HYDROLOGIC ANALYSES

Northcoast Watershed Assessment Report The NCWAP (2000) report evaluates rainfall in the Mattole based on two long-term rain gages; one in Petrolia near the basin mouth, and the other in what is called the upper Mattole (according to Figure II-1 on page 4 of the NCWAP report, this gage is actually located in the lower part of the basin at an elevation of 255 feet). Based on analyses of historical rainfall, the NCWAP report concludes there are no discernable long-term trends in annual precipitation. The NCWAP (2000) report also presents and

Mattole Low Flow Hydrology, R. Klein, 2004 7

analyzes streamflow records in the Mattole River near Petrolia (USGS Gaging Station No. 1111469000, drainage area 245 mi2). Floods, low flows, and annual yields are analyzed for long term trends. They report that there was ‘a slight decline with time in annual yields during the 50-year period and a much higher degree of variation during the last 25 years.’ Flood recurrence intervals were also analyzed, as well as low flows. They report that the 7-day low flow running average ranged from a high of 42.3 cfs (1963) to a low of 17.0 cfs (1977). They also report a ‘slight overall decline in low flow since…1951.’ and suggest this may be attributed to increased water use. They conclude by reporting that ‘streamflow data within the region do not show any distinct long-term increase or decrease in annual runoff.’ Since the NCWAP analyses were done, three additional years of data have been collected. While the low-flow frequency analysis was not re-done with these newer data, Figure 1 plots the 2001-2003 7-day low flows for both the Petrolia and Ettersburg gages on the NCWAP frequency estimates (reproduced from the NCWAP 2000 report). The Ettersburg frequency estimates were derived by multiplying the Petrolia discharges by the mean 7-day low flow discharge ratio of 0.257 based on the 2001-2003 data record. The 2002 7-day low flow was the lowest on record for the 50-year period of data collection. The 2003 low flow was substantially higher due to much higher than normal rainfall the preceding April (2003), which was characterized by numerous small to moderate rainfall events.

Figure 1. Mattole River near Petrolia (No. 11469000; DA = 245 mi2) and near Ettersburg(No. 11468900; DA = 58.1 mi2) 7-day minimum low flow frequency

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2001: 17.2 cfs

2002: 14.0 cfs

2001: 4.80 cfs 2002: 3.96 cfs

Petrolia

Ettersburg

2003: 26.14 cfs

2003: 5.16 cfs

Mattole Low Flow Hydrology, R. Klein, 2004 8

As shown, the 2001-2003 data plot at very different positions in Figure 1. 2001 was quite dry, plotting near the 80-year return period on the NCWAP frequency plot, and 2002 was drier still, plotting well beyond the 100-year return period, while 2003 was far wetter, but still slightly below the 1951-2000 mean 7-day low flow of 28 cfs. While the true frequencies of the 2001-2003 data cannot be precisely evaluated using the 1951-2000 analysis, their positions on Figure 1 indicate their relative magnitude within the long term record.

Further Analyses of Low Flows To further examine low flows and rainfall-runoff relationships, several simple data analyses were performed that differed from those in the NCWAP (2000) report. First, mean monthly discharge for the Petrolia gage for the period 1965-2004 was plotted for the driest months of the year in Figure 2 (this period was chosen to coincide with the mean monthly rainfall data available for this project). Although the period is too short to examine long-term trends, it illustrates the general decline of summer low flows of the past decade. Since 1987, September average flows (the most common minimum low flow month) have been near the low end of the longer term values, with low flow conditions being most acute since 1997. In Figure 3, these same data are expressed in terms of the percentage of average monthly discharge (departure) for the 40-year record. As shown, with one exception (1991), average (mean) September discharge has been below the 40-year average since 1987, a run of 17 years. Monthly average discharges for the other typically-dry months (July, August, and October) are similarly low, with the present dry season (July and August, 2004 are included in Fig. 3) shaping up to be another below-average low flow season.

Figure 2. Mean monthly discharge during dry months for the Mattole River near Petrolia, 1965-2004

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July (LT Mean = 75 cfs)

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October (LT Mean = 133 cfs)

Mattole Low Flow Hydrology, R. Klein, 2004 9

Figure 3. Departures from 1965-2004 mean monthly discharges for the Mattole River near Petrolia

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July (LT mean = 75 cfs)August (LT mean = 46 cfs)September (LT mean = 56 cfs)October (LT mean = 133 cfs)

One component of this analysis was to examine relationships between spring rainfall and low summer and fall flows. To accomplish this, a series of rainfall-runoff analyses were performed on the Petrolia data where antecedent (prior) rainfall for varying lengths of time was regressed against low flows. In Figure 4, the minimum 7-day low flows for 1966 to 2003 are plotted against antecedent rainfall for the 1 to 9 month period leading up to and including the low flow event. Note that the NCWAP (2000) 7-day low flows were used for the 1966-2000 period, and new values were calculated for the 2001-2003 period (not available at the time of the NCWAP analysis). Best fit lines are plotted along with regression equations and coefficients of determination (R2), with the period yielding the highest R2 shown in bold font. The NCWAP data analysis was done on a water year (Oct-Sep) basis, which splits the minimum flow season in some years (i.e., in some years, the 7-day minimum low flow occurred in October). Thus, in some years, the minimum flow on a water year basis was not the minimum for the dry season (July-Oct, typically) and there may be two 7-day minimum low flows reported for a single dry season. For years where this occurred, the higher of the two minimums was omitted for Figure 4, thus the data set used was smaller (by a few years) than the period of record suggests. This could not be avoided using the NCWAP data set, but if/when a full re-analysis of 7-day low flows is undertaken, the ‘year’ should be defined in a way that does not split the low flow season (analysis on a calendar year basis would accomplish this).

Mattole Low Flow Hydrology, R. Klein, 2004 10

Figure 4. Antecedent rainfall and 7-day minimum low flows in the Mattole River, 1966-2003.

1-month:y = 2.1749x + 24.911

R2 = 0.0313

2-month:y = 3.4608x + 23.511

R2 = 0.2374

3-month:y = 2.5591x + 23.373

R2 = 0.2247

4-month:y = 0.813x + 24.159

R2 = 0.0775

5-month:y = 0.388x + 24.206

R2 = 0.1182

6-month:y = 0.1813x + 24.167

R2 = 0.0658

7-month:y = 0.1459x + 23.296

R2 = 0.0696

9-month:y = 0.0903x + 23.18

R2 = 0.0447

9-month:y = 0.1039x + 21.676

R2 = 0.0829

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As indicated in Figure 4, no strong relationship is apparent between antecedent rainfall and the 7-day minimum low flow. The strongest relationship was with 2-month rainfall (R2 = 0.2374), but this is not considered significant (generally, an R2 of 0.7 or greater is sought in hydrological analyses as potentially indicative of a causal relationship, although other considerations are taken into account as well). It should be kept in mind that significant rainfall can occur in any month of the year, although it is not common in the dry flow months. Some of the scatter in the data in Figure 4 can be attributed to summer rainstorms that can cause discharge to spike and may slow subsequent summer low flow recession. In Figures 5-8, antecedent rainfall is plotted against average monthly discharge for the dry months (July-Oct) and linear regression model outputs are shown as in Figure 4. Strong relationships were observed for August and September average monthly discharges (Figs. 6 and 7), with the rainfall occurring since July yielding the strongest relationship in each case. As with Figure 4, some of the scatter (and low R2 values) is attributable to summer rain storms interrupting low flow recession. Many other sources of scatter may be at work in the data set, such as variable water withdrawal rates, climatic factors (temperature and humidity), sedimentation levels in the channel bed at the gaging station, etc. But it appears that for the data represented in Figures 5-8, rainfall in the summer months is of dominant importance in low summer flow rates, although rainfall during this period is quite unreliable.

Mattole Low Flow Hydrology, R. Klein, 2004 11

Figure 5. Antecedent rainfall and July discharge for the Mattole Rivernear Petrolia, 1966-2003.

Jan-Jul:y = 0.9837x + 38.735

R2 = 0.175

May-Jul:y = 12.176x + 46.93

R2 = 0.5094

Apr-Jul:y = 5.2567x + 41.479

R2 = 0.4493

Feb-Jul:y = 1.4591x + 38.611

R2 = 0.2018

Mar-Jul:y = 2.4373x + 37.813

R2 = 0.2865

Jun-Jul:y = 3.8399x + 73.053

R2 = 0.0084

Jul:y = 26.13x + 73.264

R2 = 0.0381

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Figure 6. Antecedent rainfall and August discharge for the Mattole Rivernear Petrolia, 1966-2003.

Jan-Aug:y = 0.7041x + 19.155

R2 = 0.1512

Feb-Aug:y = 1.1715x + 15.63

R2 = 0.2238

May-Aug:y = 7.2043x + 25.656

R2 = 0.4408

Jul-Aug:y = 17.994x + 35.621

R2 = 0.769

Jun-Aug:y = 13.686x + 30.582

R2 = 0.5227

Mar-Aug:y = 1.8833x + 15.812

R2 = 0.3032

Apr-Aug:y = 3.1261x + 24.162

R2 = 0.2957

Aug:y= 19.864x + 37.145

R2 = 0.7562

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Mattole Low Flow Hydrology, R. Klein, 2004 12

Figure 7. Antecedent rainfall and September discharge for the Mattole Rivernear Petrolia, 1966-2003.

Jun-Sep:y = 24.052x + 5.9363

R2 = 0.6393

Mar-Sep:y = 2.3032x + 16.631

R2 = 0.0853

Feb-Sep:y = 1.5047x + 15.771

R2 = 0.073

Aug-Sep:y = 27.454x + 17.57

R2 = 0.8019

Jul-Sep:y = 26.8x + 15.222

R2 = 0.8045

Apr-Sep:y = 4.4787x + 20.419

R2 = 0.1201

May-Sep:y = 13.82x + 3.5514

R2 = 0.4287

Sep:y = 29.1x + 28.702

R2 = 0.6384

Jan-Sep:y = 0.813x + 24.425

R2 = 0.0403

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Figure 8. Antecedent rainfall and October discharge for the Mattole Rivernear Petrolia, 1966-2003.

Mar-Oct:y = 6.0475x + 11.61

R2 = 0.074

Apr-Oct:y = 14.195x - 24.926

R2 = 0.1644

Jul-Oct:y = 39.029x - 54.029

R2 = 0.5882

Sep-Oct:y = 41.597x - 42.203

R2 = 0.6282

Aug-Oct:y = 39.112x - 49.666

R2 = 0.5745

May-Oct:y = 28.317x - 66.521

R2 = 0.397

Jun-Oct:y = 36.335x - 61.318

R2 = 0.5296

Oct:y = 48.979x - 27.638

R2 = 0.6235

Feb-Oct:y = 3.5943x + 27.061

R2 = 0.0517

Jan-Oct:y = 1.3059x + 80.108

R2 = 0.0118

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Mattole Low Flow Hydrology, R. Klein, 2004 13

Table 3 lists coefficients of determination for the regression models shown in Figures 5-8, with the strongest in each suite of models (for dry season each month) shown in bold font. Strong relationships are exhibited between rainfall beginning with the month of July through August and September with their respective mean monthly discharges.

Table 3. Coefficients of determination (R2) for regressions of antecedent rainfall on mean monthly discharge for the Mattole River near Petrolia, 1966-2003.

July August September OctoberJanuary 0.17500 0.1512 0.0403 0.0118February 0.20180 0.2238 0.0730 0.0517

March 0.28650 0.3032 0.0853 0.0740April 0.44930 0.2957 0.1201 0.1644May 0.50940 0.4408 0.4287 0.3970June 0.00840 0.5227 0.6393 0.5296July 0.03810 0.7690 0.8045 0.5882

August --- 0.7562 0.8019 0.5745September --- --- 0.6384 0.6282

October --- --- --- 0.6235

Coefficient of Determination (R2) of Antecedent Rainfall with Mean Monthly

Discharge for PetroliaCumulative Rainfall Since:

With the installation of a continuous stream gaging station a Ettersburg in July, 2001, hydrological relationships between the upper and lower areas of the Mattole River can be examined. Figure 9 shows hydrographs for the two gages, along with cumulative rainfall and antecedent precipitation index (API; a running total of rainfall inputs to the watershed whereby previous rainfall on any given day is summed with previous daily rainfall decayed by a recession factor; 0.985 was used for this analysis based on good agreement with low flow discharge at Ettersburg) from the Thompson Creek continuous rain gage. API can be taken as an approximation of the contribution of subsurface drainage to streamflow as it varies throughout the year. It has proven useful in many types of hydrological analyses. Here, it is included to graphically illustrate how rainfall might be dispensed in terms of its contribution to streamflow. It might also be thought of as indexing the baseflow contribution to stream discharge. A close look at Figure 9 reveals the dependence of low summer flows on rainfall amounts and temporal distribution. In particular, the uncommonly high spring rainfall during 2003 gave hydrologic conditions an extra boost compared to 2001 and 2002, when spring rainfall and subsequent summer low flows were similarly low, despite considerable differences in total winter rainfall. Figure 10 presents a rough water balance for the Mattole River basin above Petrolia for 2001-2004. Water use estimates from Table 1 are used to arrive at summed water use, with irrigation uses only included during the dry months (June 1-Oct 31). Both impaired (as measured at the gage) and estimated unimpaired (measured flow minus summed withdrawals) flows are shown, with the difference equal to the summed withdrawals. Assuming no irrigation or other return flows, water use diminishes discharge by about 20% to 27% for the years shown (2000-03). Using these same assumptions, the record low flow for 2002 of 14 cfs might have been closer to 18 cfs without any water withdrawals, which most likely would have been much better for fish in the river.

Mattole Low Flow Hydrology, R. Klein, 2004 14

Figure 9. Rainfall, antecedent precipitation index, and discharge in the Mattole River, 2001-04

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Figure 10. Actual (impaired) and estimated unimpaired flows and estimated water withdrawalsfor the Mattole River near Petrolia, 2001-2004

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Mattole Low Flow Hydrology, R. Klein, 2004 15

Low flow measurements during late summer and early fall, 2004 In August and September, 2004, flows were measured by SFI staff at five sites in the Upper Mattole River basin:

Site MS1: Mainstem Mattole below Helen Barnum Creek Site MS2: Mainstem Mattole above Stanley Creek Site MS3: Mainstem Mattole below McKee Creek Site MS4: Mainstem Mattole above Bridge Creek Site SCR: Sinkyone Creek

These measurements supplement the analyses in the main body of this report that were based on flow recorded at the USGS stream gages at Ettersburg and Petrolia. Sites MS1-4 are situated in downstream order along the main stem of the river between Helen Barnum Creek at the upstream end and Bridge Creek at the downstream end. Measurements were made by collecting the flow at a confined section of the channel in a 5-gallon bucket and timing how long it took to fill the bucket. This is an accurate method as long as all surface flow is caught in the bucket. In some cases, flow was split between 2-3 channels, requiring separate measurements at each channel that were summed for total flow. Figure 11 shows the flows at each site over the measurement period. Figure 12 shows just the main stem sites as flows receded over the measurement period. Typically, flow is expected to increase with increasing drainage area. However, Figure 11 indicates the reverse between MS2 and MS4 (flow is decreasing in a downstream direction). Moreover, the two downstream-most sites (MS3 and MS4) were dry (zero flow) by Sept. 21, 2004. In Figure 12, flows can be seen to recede rapidly since late August, 2004, decreasing by 99-100% over the 1-month measurement period. This documents the critical low flow conditions in the Upper Mattole River and highlights the importance of quantitatively evaluating the effects of water withdrawals on low flows and implementing water conservation strategies should they be found to be significant. Site MS-4 is located on the mainstem just upstream of Bridge Creek. Although the southern sub-basin includes Bridge Creek, the water use estimates for the southern sub-basin given in Table 2 (totaling about 0.201 cfs) should be about the same as those upstream of MS-4. As of the first flow measurement on Aug. 28, 2004, flow at MS-4 was already one half the estimated water use upstream, and dropped to zero by Sept. 21, 2004. Although the water use estimates are very approximate and need to be improved to before making definitive statements, it appears that water use may be a significant factor contributing to the extreme low flows of the current (2004) dry season. Considering the potentially serious effects water withdrawals in the Upper Mattole River may be having on the aquatic ecosystem, this issue warrants further investigation and perhaps immediate action before such an investigation is completed.

Mattole Low Flow Hydrology, R. Klein, 2004 16

Figure 11. Low flows at five sites in the Upper Mattole River, 2004

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Figure 12. Late summer flow recession in the Upper Mattole River, 2004.

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Mattole Low Flow Hydrology, R. Klein, 2004 17

PRELIMINARY CONCLUSIONS AND RECOMMENDATIONS Although this report is only a preliminary analysis, several conclusions can be made: 1) Based on low summer and fall flows, a long-running drought has persisted in the Mattole River since

1987, with only one above average low flow season (1991) since then. The drought has been most acute from 1997 to the present, despite a wet spring in 2003. In late summer, 2004, flows in the Upper Mattole River mainstem declined by 99-100% over a 1-month period (Aug. 28 through Sept. 28, 2004) and declining to zero flow at two locations by Sept. 21, 2004. Although no long term discharge records exist for this area, these conditions are similar to anecdotal observations of low flows in 2002 and may be exacerbated by human water use.

2) Summer and early fall rainfall appears to be more important to low flows than late winter and spring

rainfall. However, the uncommonly high spring rainfall during 2003 appeared to measurably augment subsequent summer low flows compared to 2001 and 2002, when spring rainfall and subsequent summer low flows were similarly low despite considerable differences in total winter rainfall. An analysis that excludes years with significant summer rain might reveal more dependence on longer-term (e.g., spring) antecedent rainfall.

3) Estimated water use represents a significant proportion (as much as 27%) of the discharge measured

at Petrolia during low flow years. From the flows measured in Aug. and Sept., 2004, water use in the southern sub-basin likely represents a much larger proportion of low summer flows. Improved estimates of water use are needed to verify this, however, this preliminary assessment suggests that water withdrawals may be reducing flows to the point of creating extremely stressful and/or lethal conditions for fish.

Recognizing that this report presents only a preliminary analysis of the low flow problem in the Mattole River, the following offers initial recommendations for getting started on measures for addressing the problem and describes a more in-depth study that would be needed to develop site-specific assessments and remedies. If actual withdrawals can be reliably quantified, then tributaries or stream reaches exhibiting hydrologically-stressful conditions for fish can be evaluated for potential benefits to be derived from water conservation and storage capacity increases.

Reducing Dry Season Demand Of all the possible options for alleviating excessively low flows, reducing demand, particularly during the dry season, is likely to be the most viable in the near term. There are a myriad of ways in which demand can be reduced, but they fall into two general categories: • Implementing water conservation practices, and • Increasing water storage capacities. As mentioned earlier, domestic water systems in the Mattole are known to have leaks and lack suitable controls preventing tank overflow. These are the two most obvious, and probably least painful (in terms of cost and lifestyle change), actions to take. Beyond that, domestic use can be further reduced by the list of household water conservation measures we have come to be familiar with (e.g., low-flow toilets and shower heads, water efficient appliances, drought-tolerant landscaping, drip irrigation systems for gardens, etc.). Implementing these measures will be far easier if accompanied by a locally sponsored public education program and subsidized equipment and supplies and perhaps labor. Agricultural water conservation practices (e.g., mulching row crops, drip irrigation, modern off-channel stock watering

Mattole Low Flow Hydrology, R. Klein, 2004 18

facilities, etc.) are also well established, and could potentially save a lot of water if supported by public outreach and incentives for implementation. Increasing the storage capacities of both domestic and agricultural users, while not reducing annual demand, can reduce dry season demand significantly. While low-head earthen dams were commonly used for stock watering ponds (and still are), they are subject to evaporative losses and may be infeasible for most applications in today’s regulatory climate. Storage tanks, however, offer a viable and economical means to increase storage capacity. As with water conservation measures, a user-friendly public education program coupled with cost incentives and subsidies could greatly enhance the storage capacity for both domestic and other water users. This could go a long way toward shifting the timing of stream withdrawals from the dry season to wetter times of the year.

Watershed Restoration and Recovery Watershed restoration has been a high priority for many Mattole residents for some time, consisting chiefly of tree planting, road upgrading and road decommissioning. These actions will accelerate the recovery of stream channels from aggradation by reducing erosion. However, there is no getting around the fact that aggradation will be with us for many decades, if not centuries to come in the lower reaches of the main stem and larger tributaries. But in the smaller tributaries where erosion prevention and control is taking place, the benefits will come sooner. While road decommissioning or upgrading will reduce sedimentation threats through time, this will be a slow process owing to the expense of road decommissioning and the many miles of road within the watershed. Thus, there will be continued erosion from roads and sediment delivery to channels, adding to that already stored in channels and delaying channel recovery despite the best efforts of restorationists. Further, ongoing timber harvest will also add to erosion and sedimentation volumes, despite the considerable improvements in harvest practices in recent years over those used earlier. Consequently, although watershed restoration is extremely important, basin-wide recovery cannot be expected for decades or centuries. However, in tributaries where restoration activities are focused, channel recovery times can be significantly decreased. Tributaries with the high potential fisheries value should be high on the priority list for restoration in order to have the most significant benefit to fish in the near term.

In-depth Assessment It was requested that a preliminary study proposal be developed to examine in greater detail relationships between Mattole River southern sub-basin low flows and water use. Such a study would be composed of two parts; Part A) an inventory of water rights and actual water use and development of a data base of GIS layers, and Part B) a hydrologic study that takes data from Part A, gathers additional data from field measurements in selected main stem reaches and tributaries of the southern sub-basin, and quantifies the effects of water withdrawals on streamflow using a water balance approach as well as other analysis tools. These two components are described below and an estimate of hours by positions is presented in Appendix A.

Part A: Water Use Inventory Although locally-derived estimates of water use were prepared for this analysis, more accurate estimates are needed to provide results of sufficient reliability to support a detailed hydrologic analysis (Part B). These estimates would be derived from a complete, spatially-linked and attributed inventory of water rights as recorded by the State Water Resources Control Board along with a household-to-household canvassing of water systems (type of source, pumping and plumbing components) and withdrawal rates to quantify domestic use. In addition, an inventory of irrigated farm and pasture lands, including type of source (surface water, well), pumping and plumbing components, actual withdrawal rates, and an inventory of all other uses (municipal, timber harvest (road watering for dust control), and other industrial

Mattole Low Flow Hydrology, R. Klein, 2004 19

and commercial uses) with similar attributes needs to be conducted. As with the data used in the NCWAP (2000) report, an air photo analysis using recent air photos would help immensely with the compiling information on irrigated farms and pastures. For compiling water rights information, the raw data presented in the NCWAP study could be used. However, it may be beneficial to also research the records kept in Sacramento (statements of use, etc.) for a more exhaustive information base. The inventory could rely on both paid personnel as well as volunteers, with trusted members of the community having the greatest chance of cooperation with landowners. A lot of time will be required for getting the cooperation of landowners and then conducting the field inventory of use and withdrawal facilities, and this is reflected in the estimates of hours in Appendix A.

Part B: Hydrologic Analysis With information supplied from Part A, a key component of a water balance will be quantified. In addition, records of rainfall presently maintained in the southern sub-basin provide another important information source. Since summer rainfall events seem to have a large effects on summer low flows, placement of inexpensive plastic storage rain gages in study tributaries will allow the spatial variability of rainfall to be accounted for in the analysis of low flows. An impediment to precision in a water balance for the southern sub-basin is the lack of continuous streamflow information; the Ettersburg gaging station (drainage area = 58.1 mi2) is downstream several miles form the southern sub-basin boundary (drainage area = 26 mi2). If possible, it would be highly beneficial to expand the study area to include the entire area above the Ettersburg gaging station, an approximate doubling of the contributing drainage area, so that the study can rely on data provided from this gage without having to synthesize streamflow for the southern sub-basin. In the event that this cannot be done, it will be necessary to install a continuous low flow stream gage at the southern sub-basin boundary, thus increasing costs. However, a low flow stream gage is far cheaper to install and operate than one for measuring year-round flow. Unfortunately, the Ettersburg gage is at risk of being shut down by the USGS due to diminishing cooperative funding contributions from the DWR. It is recommended that a vigorous attempt be made to secure continued DWR funding, find another funding source, or have local groups (e.g., MRC, MSG, SFI) continue operation of the gage, at least for low flows. If this is done, the time estimates for Parts A and B in Appendix A will likely increase by about 50%. The tasks needed to conduct a detailed hydrologic investigation are briefly described in Appendix A. To summarize, they include updating the analyses provided in the NCWAP (2000) report with more recent data (2001-2004), computing a water balance using updated hydrologic data and water use inventory data (from Part A), and conducting a series of field investigations directed at quantifying flow rates as they vary within the study area (both on the main stem and several tributaries) and how the timing and rates of water withdrawals affect local streamflows. Site selection must be done at the beginning of the study, however, there are several candidate sites that are already known. These are: • Baker Creek: a stream of known juvenile salmonid rearing and known to have dry reaches during

drought periods. • Anderson Creek: a stream of known juvenile salmonid rearing but apparently higher flow rates than

Baker Creek, making it a good candidate for data collection to compare with Baker and perhaps other creeks.

• Thompson Creek: a large tributary with very limited, but cooperative water users, allowing access to reliable water use rates so that local effects of withdrawals can be accurately evaluated.

Mattole Low Flow Hydrology, R. Klein, 2004 20

• Main stem Mattole below Helen Barnum Creek: a point of bedrock outcrops that would provide streamflow data without the influence of channel aggradation. This corresponds to Site MS-1 occupied in 2004 (discussed earlier).

• Ettersburg gaging station: a location with existing continuous data collection that can be evaluated for channel aggradation effects by comparison with nearby bedrock-controlled reaches.

• Other main stem reaches: several other reaches along the main stem will be selected by field reconnaissance to include reaches with and without direct withdrawals to quantify effects of main stem withdrawals. Three flow measurement sites of 2004 (MS2-4) would be good candidates since data already exist for these sites.

• Other tributaries: several other tributaries may be selected to evaluate effects of water withdrawals for road watering for dust control and perhaps other uses.

The data collection will consist of simultaneous discharge measurements at paired locations in a control/treatment study approach, typically relying on upstream/downstream pairs (e.g., discharge will be measured both upstream and downstream of the major water withdrawal site in lower Thompson Creek during withdrawal periods). Inexpensive stage recorders will also be needed to track streamflow continuously throughout the low flow study period, at least at a subset of the study reaches. Data processing and analysis will follow field work, and a report will be prepared detailing results and conclusions, along a suite of recommended actions to direct water use modifications, where and when they appear to provide significant benefits to fish, in a cost efficient manner. Another necessary component to understanding the effects water use in the Mattole River basin is to continue and augment ongoing work on fish observations. This is important for determining where and when juvenile salmonids are experiencing difficulties due to low streamflows and where they are not, and using this information for evaluating the most urgent locations and cost-effective methods for alleviating problems where feasible. This effort could be called Task C and should be conceptualized by fisheries biologists familiar with low flow habitat conditions and the attendant stresses on fish. LITERATURE CITED Keppeler, E.T. 1998. The summer flow and water yield response to timber harvest. In Proceedings of the

Conference on Coastal Watersheds: The Caspar Creek Story. May 6, 1998. Ukiah, Calif. USDA Gen. Tech. Report PSW-GTR-168. Pp. 35-43.

Madej, M.A., and V.L. Ozaki. 1996. Channel response to sediment wave propagation and movement,

Redwood Creek, California, USA. Earth Surface Processes and Landforms. v. 21. pp. 911-927. North Coast watershed Assessment Program (NCWAP): Mattole River Assessment. 2000. Appendix C:

Hydrology. 26 p.

Mattole Low Flow Hydrology, R. Klein, 2004 21

APPENDIX A: STUDY PROPOSAL TIME ESTIMATES FOR MATTOLE RIVER LOW FLOWS

Mattole River Low Flow Study Proposal Budget

Part A: Water Use Inventory PH HT HA CO CT RSTask A1. Develop information base and GIS layer of water rights diversion points and maximum diversion rates 80 80Task A2. Develop information base and GIS layer of households, no. of occupants, garden size, irrigation method, storage capacity, leak rate, and method of withdrawal (surface vs ground water) 240 160Task A3. Develop information base and GIS layer of irrigated pastures and farms with crop types and method of withdrawal (surface vs groundwater). 80Task A4. Develop information base and GIS layer of other water uses (business, municipal, etc.), location and method of withdrawal (surface vs groundwater) 80Task A5. Interrogate CDF records of THPs and unsurfaced road miles used to estimate water withdrawals for dust control, fire suppression. 80 160Totals for Part A 0 0 0 400 320 240

Part B: Low Flow Hydrologic AnalysisTask B1. Update hydrological analyses of low flow 80 40

Task B2. Compute water balance based on recent data 40Task B3. Conduct field data collection on tributary flow rates to compare natural vs impaired flow (three tributaries in southern sub-basin) 20 40 40

Task B4. Conduct field data collection on main stem flow rates to compare natural vs impaired flow (three reaches in southern sub-basin) 20 40 40

Task B5 Conduct field data collection on main stem flow rates to compare bedrock vs gravel bedded reaches (three reaches in southern sub-basin) 20 40 40

Task B6. Process field data and input to spreadsheet 60Task B7. Analyze discharge data and quantify effects of water withdrawals and channel sedimentation 40 60Task B8. Report preparation 40 80Totals for Part B 260 360 120 0 0 0

Position: CodePrincipal Hydrologist PHHydrologic Technician HTHydrologic Assistant HACommunity Outreach Specialist COComputer Technician (GIS capabilities) CTRecords Searcher RS

Estimated Hours by Position Code

Mattole Low Flow Hydrology, R. Klein, 2004 22