Stream Restoration in Ephemeral Gullies
Water Quality and Quantity Benefits
Joe Berg, Biohabitats, Inc.
[email protected]
Sediment Supply
Channel Adjustment to Stormwater Flow
Source: Expert Stream Panel Report, Stack 2013
Ephemeral Gully Restoration Approach
Regenerative Design
Pre-existing erosion damage
Sand seepage bed
Riffle Grade Controls
Tributary to Rock
Creek
Washington, DC
February 2011
Pre Restoration
~8 ft Incised
Minimal to no baseflow
Tributary to Rock Creek
Washington, DC
October 2011
Connected to Riparian Zone
Intermittent to Perennial Flow
5-ft incised
No water
22-ft incised
Adverse effect on
shallow groundwater
and downstream flows
Source: Solange Filosa,
University of Maryland
Source: Solange Filosa, University of Maryland
‘Super storm’ Sandy
http://cuencalosojos.org
Cuenca Los Ojos Foundation
“Restoring habitat through an ancient tradition of slowing
erosion and harvesting water -- water that would otherwise
rush over a desiccated landscape. Bringing water back to the
land has resulted in remarkable vegetation changes, which in
turn has increased populations across the wildlife spectrum.”
•500+ earth berms,
•54 large gabion dams
•~30,000 trincheras (loose rock structures)
•1,920 acres of riparian habitat restoration
•5 Miles of perennial stream restored in this arid region
Beaver dams very common on landscape—Useful Analog?
Marshall, K. N., N. T. Hobbs, and D. J. Cooper. "Stream hydrology limits
recovery of riparian ecosystems after wolf reintroduction." Proceedings.
Biological sciences/The Royal Society. Vol. 280. No. 1756. 2013.
The strongest explanation for why the wolves have made less of a difference than
we expected comes from a long-term, experimental study by a research group at
Colorado State University. This study, which focused on willows, showed that the
decades without wolves changed Yellowstone too much to undo. After humans
exterminated wolves nearly a century ago, elk grew so abundant that they all but
eliminated willow shrubs. Without willows to eat, beavers declined. Without
beaver dams, fast-flowing streams cut deeper into the terrain. The water table
dropped below the reach of willow roots. Now it’s too late for even high levels of
wolf predation to restore the willows.”
Questions?
[email protected]