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Lesser Goldfinch male

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East Garden Grove –Wintersburg Channel/Bolsa Chica Wetlands

The watershed encompasses 27.3 square miles. The East Garden Grove - Wintersburg Channel and the Freeman Creek Channel are the tributaries to the watershed. Bolsa Chica is located in the unincorporated portion of Orange County, surrounded by the City of Huntington Beach and bordered to the west by the Pacific Coast Highway. There are 900 acres of wetland habitat (an estimate that does not include wetland habitat outside of the LCP area). Historically, Bolsa Bay encompassed 2,300 acres of tidally influenced wetlands and large expanses of freshwater marshes in the interior portion of the bay that were fed by artesian springs of the Freeman River.

Although once an extensive tidal marsh system, much of the marsh area was removed from tidal influence. Outer Bolsa Bay is directly connected to Huntington Harbor, which is the only area fully open to tidal influence. Inner Bolsa Bay and the Ecological Reserve have a controlled tidal regime (through the use of flood gates to Outer Bolsa Bay).

Despite land-use activities within the watershed, the Bolsa Chica wetlands complex is an incredibly diverse ecosystem that includes a range of invertebrate, reptile, bird, fish and other species. A compilation of 15 surveys from 1970 through 1993 identified 206 species, including 129 water related species and 32 special status species. Twelve species have been observed nesting on site, including the elegant tern, burrowing owl, California horned lark, Beldings savannah sparrow, western snowy plover, California least tern, black skimmer, and loggerhead shrike. In 1993 bird surveys found common loon, American white pelican, California brown pelican, double crested cormorant, reddish egret, elegant tern, white-face ibis, light-footed clapper rail, western snowy plover, long-billed curlew, California gull, California least tern, black tern, elegant tern, black skimmer, Northern harrier, short-eared owl, loggerhead shrike, saltmarsh common yel-lowthroat, Belding’s savannah sparrow, tricolored blackbird, borrowing owl, and California horned lark. A 1990 Invertebrate, amphibian, reptile and mammal study identified the San Diego coast horned lizard, southwestern pond turtle, silvery legless lizard, salt marsh shrew, American badger, and Black-tailed jackrabbit. A 1993 survey identified the Southern tarplant.

Since the 1960’s numerous proposals have been made for the Bolsa Chica marsh and adjacent planning areas. In 1973 the State gained possession of approximately 300 acres of wetlands. In 1978, 163 acres of the State Ecological Reserve were returned to tidal action. In 1996, an amended LCP Land Use Plan and Implementing Actions Program was certified by the California Coastal Commission. These documents provide specific proposals for development of the mesa and lowlands.

By 1992, the watershed was 85 percent urbanized. Possible soil contamination and poor water quality from run-off negatively impact native marsh plants. Subsidence of land surface may reduce existing habitats. Much of the wetlands areas continue to degrade due to lack of tidal inundation.

The California Coastal Commission rejected a residential development in 2001 on the upland portion of the wetlands. The relative acreage and extent of development and undeveloped portions of the wetlands remain an issue of contention.

Talbert Channel/Huntington Beach Wetlands

The watershed encompasses 13.3 square miles of area that includes primarily the Talbert/Huntington Beach flood control channels. The Huntington Beach Wetlands are located in the City of Huntington Beach between the Santa Ana River and Beach Boulevard along the eastern side of the Pacific Coast Highway. The total wetland

acreage is 115, a remnant of an extensive 2,900 acre salt marsh that existed at the mouth of the Santa Ana River. The marsh was filled in between 1950 to 1969 for urban development and a flood control. Riparian forests of the Santa Ana River have been lost to channelization and flood control.

A 25-acre site, known as Talbert Marsh, at the southwestern end of the wetland area, adjacent to the Santa Ana River, has been enhanced. The Talbert flood control channel has been reconfigured to flow through this marsh.

The Huntington Beach wetlands are isolated from surface tidal exchange except that portion of the Talbert Marsh that has been restored to full tidal action. The wetlands characteristics of the remaining marshes are maintained through fluctuations in the local water table, direct precipitation and limited urban run-off.

Water quality from urban run-off, the close proximity of industrial plants, and traffic volumes along the Pacific Coast Highway contribute to environmental stress of the Talbert marsh. The other sites along the Pacific Coast Highway continue to degrade due to inappropriate recreational uses, disconnection from tidal action, and urban encroachment.

In 1989 the Talbert and Huntington Channels were upgraded and retention basin installed upstream which will affect sediment transport and peak flood flows through Talbert Marsh. There is currently no watershed-based plan.

Santa Ana River/Mouth Estuary

The Santa Ana River is one of the largest rivers in southern California. Channelization with high levee banks and other flood control measures upstream have greatly reduced the river as a source of seasonal flood-waters to the marshes. A second tributary, the Greenville-Banning Channel joins the Santa Ana River. Flows are composed of storm water discharge and urban run-off. The two major dams are Prado Dam (1941) and Seven Oaks Dam (completed in 1998).

The wetland areas are bounded by the Santa Ana River to the west. Fairview Regional Park is to the north. To the east is the mesa and residential development of the City of Costa Mesa. The Pacific Coast Highway and residential development of Newport Beach are to the south.

In 1995, surveys for 93 species were identified of which 56 are water associated. Twelve special status species were observed, including the Snowy plover, Belding’s Savannah sparrow, osprey, Cooper’s hawk, long-billed curlew, California gull, elegant turn, black skimmer, loggerhead shrike, yellow warbler, Wilson’s war-bler, and double-crested cormorant. Earlier surveys from 1976 to 1988 of the lowlands identified the least bittern, white-faced ibis, northern harrier, peregrine falcon, and willow flycatcher.

As part of the Santa Ana River flood control project, the COE began restoration of 92 acres of marsh in 1989 as mitigation for biological impacts. In 1991, Orange County adopted an Enhancement Plan for South Talbert and Fairview/North Tal-bert parks, (renamed Talbert Nature Preserve in 1995) which

included wetland enhancement. Restoration work on the northern portion of the Preserve and around Victoria Pond were completed in 1996.

The Talbert Nature Preserve is impacted from the adjoining developed recreation areas to the north, limited flooding events, and poor quality water from the mesa urban run-off. The loss of salt marsh flora and fauna continues at the Mobil Oil site due to the absence of tidal waters.

Black-bellied Slender Salamamnder

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Elegant Tern (oiled) andBlack Skimmer

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The Santa Ana Watershed Project Authority (SAWPA) was formed in 1971 to develop a long-term plan to manage the area’s water supply, and finance and build multi-agency water projects. SAWPA historically focused on water quality and ground water. In 1994, the Authority broadened its focus and participation to include issues of flood control, wildlife resources and interaction with other water agencies.

San Diego Creek/Upper Newport Bay

The watershed encompasses 154 square miles. The two tributaries to the watershed are San Diego Creek and Bonita Creek. San Diego Creek accounts for about 80% of the Newport Bay watershed area. The other drainage areas include the Santa Ana-Delhi Channel, Big Canyon and some additional small tributaries. All of the channels empty into the Newport Bay, a coastal estuary of ecological significance known as the Upper Newport Bay Ecological Reserve. San Diego Creek accounts for over 90 percent of the sediment delivered to the Bay.

The Newport Bay once contained 13,500 acres of estuary and marsh. The lower bay was dredged during the 1940s to create Newport Harbor. The Upper Bay was diked off for salt evaporation ponds, but the ponds were destroyed in 1969 by a flood. Large volumes of sediment were deposited in the bay. Salt marsh areas filled in with sediments during successive storm seasons and tidal action was diminished. Less frequent tidal inundation also reduced the quality of the habitat. Nutrients from the watershed overwhelmed bay waters, seasonal algae blooms spread throughout the entire bay, and, as a consequence, eelgrass beds in the Upper Bay were destroyed.

Moreover, the watershed has been rapidly urbanized during the past two decades, with large tracts of agricultural land transformed into commercial and residential uses. Upper Newport Bay is located in the City of Newport Beach, Orange County. The City of Costa Mesa is along the western border and the City of Irvine is to the north.

In 1975, the 752-acre Upper Newport Bay State Ecological Reserve was established by the Department of Fish and Game. The Reserve occupies the major portion of the northern part of the Upper Bay and provides public parking and walking trails, and a small boat launch ramp. A rowing club and dredging maintenance facility are located on Shellmaker Island within the Reserve. To the east, west and north of the Bay lay industrial and residential areas including the University of California Irvine Campus 1.5 miles northeast and the Orange County Airport 1.5 miles north. To the southwest is the densely developed Newport Beach Harbor.

In 1995 surveys, 78 species of birds in Upper Newport Bay, including 66 water-associated birds and 3 special status spe-cies, were identified including 117 pairs of light-footed clapper rail, California least tern, Brown pelican, and the American per-egrine falcon. In 1991 surveys, 199 pairs of Belding’s Savan-nah sparrows were identified.

A series of sediment settlement basins were excavated in the upper portion of the Ecological Reserve (completed 1988) to reduce distribution of sediments in the Bay and increase the tidal prism. Two least tern nesting islands were built during this project to encourage nesting activity. The plan for the next phase of maintenance dredging and increased basin capacity was prepared in 1995.

There is no comprehensive watershed-based plan for the Bay and the greater water-shed. The Upper Newport Bay Ecosystem Restoration Feasibility Study (May 2000) addresses the issues related to continued sedimentation problems within the Bay, and the direct effects of sedimentation on the habitats and species that make up the ecologi-cal reserve. The study does not identify any alternative measures for the watershed. The

Corps and the sponsor have initiated a separate watershed feasibility study to develop a watershed management plan for the Bay, and to investigate site-specific restoration opportunities within the watershed (County of Orange 2000).

San Diego Creek/San Joaquin Marsh

The watershed of San Diego Creek is 105 square miles. San Diego Creek is channelized and leveed adjacent to the marsh. Only a limited amount of water enters the marsh through managed culverts. The creek is perennial. The current wetland acreage is 492. The San Joaquin Marsh is a remnant of an extensive marsh and riparian system that existed along the Santa Ana River and San Diego Creek.

San Diego Creek was dammed from 1936 to 1963 to protect the salt ponds at the upper reach of Upper Newport Bay. The Marsh was once contiguous with Upper Newport Bay, and subject to limited tidal action. In 1993 a plank dam was installed

just down stream from the southwestern corner of the marsh eliminating tidal action in San Diego Creek adjacent to the marsh.

The San Joaquin Marsh is located within the City of Irvine one half mile east of Upper Newport Bay. The Marsh is designated as a Conservation and Open Space area in the City of Irvine’s General Plan and Zoning Ordinance.

The San Joaquin Marsh is the largest coastal freshwater marsh in Southern California. The Marsh is surrounded by urban development including a golf course to the east, a business/office area to the north, residential development to the west and UC Irvine to the south. Salt marshes and Upper Newport Bay Ecological Reserve lie to the west. The San Joaquin Marsh Reserve is managed by the

University of California Natural Reserve System (UCNRS). UCNRS uses the Reserve for education and research. The San Joaquin Wildlife Sanctuary protects Thirty acres of freshwater effluent ponds.

In 1995, 75 species of birds were identified, including 49 water-associated birds and 7 special status species, including California gull, American peregrine falcon, black shouldered kite, northern harrier, white-faced ibis, Cooper’s hawk and black-shouldered kite. In 1990, surveys identified the light-footed clapper rail, California least tern, Swainson’s hawk, least bittern, tricolored blackbird, pacific tree frog, southwestern pond turtle and western fence lizard. The same year, three species of amphibians, 8 species of reptiles, and 15 species of mammals were found in the marsh, including raccoon, long-

tailed weasel, gray fox, bobcat, coyote, pacific tree frog, southwestern pond turtle, and western fence lizard.

The San Joaquin Marsh wetland complex has become severely degraded over the past decade. Pressures include: insufficient water inflow to maintain historic habi-tat types, invasion by non-native plants, segmentation of the marsh by Campus Drive, sedimentation, and poor water quality.

American Bittern

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Western Screech-Owl

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California Newt in amplexus

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This subregion is divided into 11 major hydrologic units. The wetlands and riparian habitats of the subregion include several large bays in the south, a series of coastal lagoons, and several rivers with small estuaries and substantial riparian areas. The subregion has thirteen principal surface water systems originating in the western highlands that flow to the sea. From north to south these systems are Aliso Creek, San Juan Creek, San Mateo Creek, San Onofre Creek, Santa Margarita River, San Luis Rey River, San Marcos Creek, Escondido Creek, San Dieguito River, San Diego River, Sweetwater River, Otay River, and Tijuana River (SDRWQCB 1994). Most of these surface waters are interrupted in character having both perennial and ephemeral components due to the pattern of rainfall and impoundments, which capture flow from nearly all of the streams and rivers. Most of the surface water impoundments are a blend of natural runoff and imported water.

Rapid development (e.g., urbanization) of the coastal area of this subregion has occurred since 1980. Continued development poses significant threats to the habitats and biodiversity of coastal wetlands and watersheds. Most of the lagoons of the subregion suffer from two major and interrelated problems: sedimentation and lack of tidal flow. Thousands of acres in the watersheds of each lagoon and wetland continue to be paved. The effect of these massive landscape changes is on the water-ways of the system, including the tidal channels, riparian forests, upland habitats, and marshes – all of which can be changed by land use development. Many of the subregion’s lagoons are being filled by sediment. Marshes are being smothered. Moreover, the lagoons rarely stay open and, therefore, cannot receive the necessary tidal influence.

Akin to the other subregions, there are few watershed-based management plans that have been developed to deal with the range of threats and multiple use impacts to coastal wetlands and watersheds of this subregion.

Aliso Creek

The Aliso Creek watershed is located in Southern Orange County, and encompasses a drainage area of approximately 36 square miles. The watershed extends 19 miles from the foothills of the Santa Ana Mountains to the Pacific Ocean south of Laguna Beach, and includes the tributaries of Wood Canyon, Sulphur Creek, Aliso Hills Channel, Dairy Fork, Munger Creek, and English Canyon. Residential developments within the watershed include portions of Lake Forest, Laguna Beach, Foothill Ranch, Porola Hills, Mission Viejo, Laguna Hills, Aliso Viejo, and Laguna Niguel.

The majority of the watershed is urbanized with residential development. Watershed concerns include channelization, poor surface water quality from discharge of non-point sources, loss of habitat in the floodplain, loss of riparian habitat, paving of the flood plain, decline of water supply and flows, biodiversity loss, invasive species, surface erosion, and overuse of existing resources.

The Aliso Creek Watershed Management Study (COE 1998a) provides a trend and analysis of the ecology of the watershed. The feasibility study also identifies opportuni-ties to address watershed management from a basin-wide perspective. Issues investi-

gated in the study are land use, hydrology, hydraulics, flooding, river geomorphology, erosion, sedimentation, geology, soils, water quality, groundwater, vegetation, endan-gered species, and cultural resources.

San Juan Creek/Doheny Lagoon

The San Juan Creek watershed encompasses a drainage area of 176 square miles extending from the Cleveland National Forest in the Santa Ana Mountains to the Pacific Ocean at Doheny State Beach near Dana Point Harbor. San Juan Creek is approximately 27 miles long with a peak elevation of 5,700 feet. Major tributaries of the watershed include Trabuco Creek, Horno Creek, Canada Gobernadora, Canada Chiquita, Verdugo Wash, Lucan Canyon, Cold Spring Canyon, and Hot Spring Canyon. Oso Creek, Hickey Canyon Creek, Live Oak Canyon Creek are major tributaries to Trabuco Creek. There are two major dams, Oso Reservoir and Mission Viejo Lake on Oso Creek. The watershed includes the communities of San Juan Capistrano, Mission Viejo, Laguna Hills, Laguna

Niguel and Dana Point. The communities of Rancho Santa Margarita, Dove Canyon, Coto de Caza, and Las Flores are located along the upper San Juan Creek watershed.

Development has occurred very rapidly in this watershed since 1980. The Oso Creek and Trabuco Creek watersheds have been most affected by development. Watershed concerns include channelization, poor surface water quality from discharge of non-point sources, loss of habitat in the floodplain, loss of riparian habitat, paving of the flood plain, decline of water supply and flows, biodiversity loss, invasive species, surface erosion, and overuse of existing resources.

There are 3 wetland acres in a system that once encompassed approxi-mately 300 acres in the lower 2 miles (in 1948) of the creek. The flood control channel is unzoned, and the area within Doheny State Beach, though not subject to local land use controls, is zoned recreation. The lower 2.6 miles of the creek are channelized for flood control. Conversion of the floodplain to residential and commercial uses began soon after the creek was channelized and armored in 1962. Approximately 80% of the land adjacent to the channel is in residential or commercial use. Two water treatment plants, one on each side of the river, lie just upstream of the Hwy 1 bridge (neither discharges into the Creek). A beach berm blocks the mouth

most of the time, but the subsequent build-up of water causes it to break periodically. No information is available on the degree of tidal exchange that may occur while the mouth is open.

The San Juan Creek Watershed Management Study (COE 1998b) reviews and assesses past, current activities, and trends in the watershed. The feasibility study also identifies opportunities to address watershed management from a basin-wide perspective. Issues investigated in the study are land use, hydrology, hydraulics, flooding, river geomor-phology, erosion, sedimentation, geology, soils, water quality, groundwater, vegetation, endangered species, and cultural resources.

San Mateo Creek/Lagoon

The watershed encompasses 132 square miles. The San Mateo Lagoon includes 30 acres of wetland habitat, and is located within San Onofre State Beach, just south of the San Diego/Orange County border. The lagoon and lower San Mateo Creek are leased to the State Department of Parks and Recreation, and are located on Camp Pendleton. The lagoon and portions of the creek and adjacent areas are part of San Onofre State Beach, and are known as the Trestles Natural Reserve. The railroad and Highway 5 cross the marsh and/or riparian areas.

13An excellent overview of this subregion’s wetlands is found at California Coastal Conservancy. 1989. The Coastal Wetlands of San Diego County. Oakland, CA. The section draws from this report.

V. Northern San Diego and Southern Orange County13

Allen’s Hummingbirds

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