Location

UMass Amherst

Event Website

http://fishpassage.ecs.umass.edu/Conference2012/

Start Date

7-6-2012 11:30 AM

End Date

7-6-2012 12:00 PM

Description

Fish passage restoration has historically focused heavily on creating hydraulic conditions within a channel or fishway that are favorable for upstream migration with respect to the physiology of the target fishes. This approach has proven successful for the upstream migration of adult fishes on larger rivers, but does not always translate well to the second and third order streams where the impacts of urbanization are most pronounced. In urban environments the stream hydrology and chemistry has been significantly altered to a point where miles of stream no longer support perennial flow year round. Consequently, upstream migrations can be successful, yet the young of the year and resident fish populations are stressed due to the lack of adequate baseflow. Even the most elegant fish passage or restoration project could be considered a failure if upstream rearing habitats are not sustainable. This presentation discusses two regenerative design applications to restore watershed hydrology and moderate the stream hydrograph such that the baseflows in urban channels a sustained year round and resident fish passage and rearing habitats are enhanced. The first case study is an in-channel approach that maximizes in channel pool habitat and forces frequent overbank flows to restore the water table in the upper watershed. By storing water in the upper watershed, baseflows in the lower watershed are sustained as the water seeps to the channel through shallow subsurface and hyporheic pathways. Delivering water to the lower watershed through these pathways also influences the stream temperature such that coldwater fisheries can also be enhanced. The second case study is a project aimed to mitigate the impacts of a planned development that threatened to rob the hydrology and increase water temperature in a regionally unique native trout stream. A regenerative approach to upland stormwater management was applied to mimic the sites natural hydrology and convert surface runoff to shallow subsurface flows that reduced peak flows and elongated the falling limb of the hydrograph such that baseflow and water temperatures were sustained. These applications have the ability to 1) directly restore fish passage by increasing the depth of baseflow in the channel and over obstructions and 2) enhance the success of traditional fish passage projects by creating sustainable in-stream habitats in urban channels.

Comments

Mr. Trumbauer is a restoration ecologist with 12 years of experience specializing in the assessment and restoration of stream and wetland systems. He received his B.S. in Wildlife and Fisheries Management from Frostburg State University and a M.S. in Environmental Science with a concentration in Water Resource Management from Towson University. He has focused professional career on gaining a broad understanding of river mechanics, hydrology, open-channel hydraulics, and the physical processes that shape river systems and applied this knowledge to enhance the ecological function of restoration designs in urban and rural settings. Mr. Trumbauer presently works out of the Chesapeake/Delaware Bay Bioregional office of Biohabitats, Inc. in Baltimore, MD. Biohabitats is a 50-person firm that specializes in ecological restoration, conservation planning, and regenerative design.

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Jun 7th, 11:30 AM Jun 7th, 12:00 PM

Session C7 - Regenerative design applications to sustain baseflow to enhance fish passage in urban channels

UMass Amherst

Fish passage restoration has historically focused heavily on creating hydraulic conditions within a channel or fishway that are favorable for upstream migration with respect to the physiology of the target fishes. This approach has proven successful for the upstream migration of adult fishes on larger rivers, but does not always translate well to the second and third order streams where the impacts of urbanization are most pronounced. In urban environments the stream hydrology and chemistry has been significantly altered to a point where miles of stream no longer support perennial flow year round. Consequently, upstream migrations can be successful, yet the young of the year and resident fish populations are stressed due to the lack of adequate baseflow. Even the most elegant fish passage or restoration project could be considered a failure if upstream rearing habitats are not sustainable. This presentation discusses two regenerative design applications to restore watershed hydrology and moderate the stream hydrograph such that the baseflows in urban channels a sustained year round and resident fish passage and rearing habitats are enhanced. The first case study is an in-channel approach that maximizes in channel pool habitat and forces frequent overbank flows to restore the water table in the upper watershed. By storing water in the upper watershed, baseflows in the lower watershed are sustained as the water seeps to the channel through shallow subsurface and hyporheic pathways. Delivering water to the lower watershed through these pathways also influences the stream temperature such that coldwater fisheries can also be enhanced. The second case study is a project aimed to mitigate the impacts of a planned development that threatened to rob the hydrology and increase water temperature in a regionally unique native trout stream. A regenerative approach to upland stormwater management was applied to mimic the sites natural hydrology and convert surface runoff to shallow subsurface flows that reduced peak flows and elongated the falling limb of the hydrograph such that baseflow and water temperatures were sustained. These applications have the ability to 1) directly restore fish passage by increasing the depth of baseflow in the channel and over obstructions and 2) enhance the success of traditional fish passage projects by creating sustainable in-stream habitats in urban channels.

http://scholarworks.umass.edu/fishpassage_conference/2012/June7/11