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Goals for this presentation…
• Develop strategies for adapting streams to climate impacts by
– Thinking like a watershed
– Understanding climate change impacts to watershed function
– Building resistance and resilience to habitats and trout populations
– Preparing streams for flooding
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What makes stream systems so special?
Linear habitats
Networked but easily fragmented
Subjected to disturbances from aquatic and terrestrial environments
Multi- dimensional connectivity
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Watershed Function
• Receive
• store
• release water
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Important habitats for improving watershed function for stream resiliency
• Riparian areas
• Wetlands
• Mountain meadows
• Floodplains
• Stream channels
• Intermittent streams
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Even small, intermittent streams can be crucial
The importance of intermittent streams to developing cold-water patches in receiving warm rivers.
Cold-water patches present at 53% (36 of 68) of tributary confluences – even when surface stream channels were dry.
Ebersole, J.L. et al. 2015. Predicting the occurrence of cold-water patches at intermittent and ephemeral tributary confluences with warm rivers. Freshwater Science 34:111-124.
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Kaushal et al. 2010: Rising stream and river temperatures in the U.S. Frontiers in Ecology and the Environment 8:461-466.
1960s to 2007
• Hudson River
• Delaware River
• Brandywine Creek
• Gunpowder River
• Potomac River
• Patuxent River
Combination of increased urbanization and climate change
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Increasing large storms: largest storm at each station increased average of 10% from 1948 - 2012
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Change in heavy precipitation: 1958 - 2011
Response to Tropical Storm Irene and Repeated New England Flooding: 2011
Disturbances and human
responses to disturbance
extend across jurisdictions
and far downstream
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What does this mean for the Northeast?
1958-2012
2041-2070 average
1971-2000 average
• Warmer temperatures
• More heavy precipitation events
• Rising sea level
Source: National Climate Assessment, 2014
What to do? • Increase resilience in trout populations and habitats
– Increase small populations
– Increase cold-water refuge habitats
– Improve habitat conditions
• Reconnect stream network
• Remove existing stressors
• Increase redundancy – number and distribution of populations
Resilience: the capacity of a system to respond to disturbance by resisting damage
and recover quickly
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Increasing stream resilience to disturbance
Disturbance Strategy Restoration Action
Drought Keep water in headwaters longer; connect and recharge aquifers; and increase refuge habitat
1. Restore headwater meadows and wetlands 2. Increase meanders 3. Increase the number and size of deep pools
Floods Increase natural capacity of streamside habitats to absorb and dissipate increased flows
1. Reconnect and restore floodplains 2. Improve culverts for higher flows
Wildfire Create large wet zones along stream that are resistant to burning; increase width of riparian and wet meadow areas
1. Increase width and lushness of riparian areas 2. Slow flows, remeander to increase shallow groundwater in meadows 3. Introduce beavers
Middle Farrer Brook culvert removal November 6—7, 2007
Before (looking upstream)
5’ diameter CMP; 2.8’ drop
After (looking downstream)
After (looking upstream)
Road retired; valley fill removed
Before (looking downstream) 16
Long Mountain Brook culvert replacement September 22—29, 2008
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Long Mountain Brook culvert replacement
Before – September 22, 2008 (looking upstream)
6’ diameter pipe; 1.2’ drop
After – September 29, 2008 (looking upstream)
22’ x 8’ embedded aluminum box
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Lower Pike Brook culvert removal November 5, 2008
Before (looking downstream)
7’ diameter pipe; 1.0’ drop (at inlet)
After (looking downstream)
Road retired; valley fill removed
Before (looking upstream) After (looking upstream) 19
Johnson Brook culvert remediation June 22—24, 2009
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Johnson Brook culvert remediation June 22—24, 2009
Before (looking downstream)
4’ diameter pipe; 1.3’ drop
After (looking downstream)
26’ clear span; pre-fabricated steel bridge
Before (looking upstream) After (looking upstream) 21
Slide Brook culvert remediation May 12—26, 2010
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Slide Brook culvert remediation May 12—26, 2010
Before – July 20, 2006 (looking upstream)
6’ diameter pipe; 3.4’ drop
After – May 26, 2010 (looking upstream)
42’ clear span; pre-manufactured steel bridge
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Upper Farrer Brook culvert remediation August 23—24, 2010
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Before – August 23, 2010 (looking upstream)
Two 2’ diameter CMPs; 0.9’ drop
After – August 24, 2010 (looking upstream)
26’ clear span bridge installed upstream; fill removed
Upper Farrer Brook culvert remediation
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Project Design: Crow Creek, Idaho
• Yellowstone cutthroat
• Channel straightened for hay cultivation
• Loss of habitat, especially pools
• Increased summer temps
• More frequent flooding and erosion
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Photo of Crow Creek just after diversion of water into new channel
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Crow Creek Restoration Results
Stream Gradient (%)
Sinuosity Stream Length (ft.)
Number of Pools
Before 0.7 1.1 3,304 9
After 0.4 2.4 6,474 86
Maggie Creek – historically a large interconnected LCT system
Decades of intense hot season
grazing
Fragmentation from
culvert barriers
1993 BLM, Newmont Mining Corps and
several and private ranches initiated
the Maggie Creek Watershed
Restoration Project (MCWRP)
Goal: enhance 82 miles of stream
and 2000 acres riparian habitat
and 40000 acres of upland areas
•Fencing
•Prescription grazing
•Seeding/planting
1980
2011
Mainstem Maggie
Creek
1980
2011
32 Open Range
Consulting
Remote sensing to document project effectiveness
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BLM/TU on-the-ground monitoring
• Increased sinuosity
• Increased riparian vegetation
• Development of quality pools
• Improved channel substrates
• Narrowing and deepening of the stream channel
Mainstem 1980 2006 2011
Sediment capture has improved greatly
Newmont Mines, Inc
One other very important
partner…
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Lahontan cutthroat trout habitat in southeastern Oregon following Holloway wildfire: 245,505 acres burned
Left: stream segment without beavers; right: with beavers
All culverts replaced
in fall 2005
x Beaver was completely
isolated = focal stream
Beaver creek before culvert removal
Beaver creek after culvert removal
Presence of larger, migratory Lahontans
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We can improve water supplies through stream and wetland restoration
• Improving water quality by slowing flows, improving riparian function and decreasing erosion
• Improving timing of water delivery and late-season stream flow by holding water in headwaters and mountain tops for longer periods
• Increasing resistance to floods and drought by reconnecting streams to floodplains and restoring wetlands
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My thanks to the following…
• BLM, Elko District
• U.S. Forest Service
• National Fish and Wildlife Foundation
• Open Range Consulting
• My co-authors Helen Neville, Amy Haak, Warren Colyer, Seth Wenger, Stan Bradshaw
