Western Run Stream Restoration
This stream restoration project incorporated the realignment of approximately 362 linear feet (LF) of Western Run. The intent of this project was to reduce erosion along the stream bank, create a stable riffle-pool sequence, establish riparian and stream bank vegetation, and improve aquatic habitat for wildlife—in particular, trout. Western Run exhibited extreme bank erodibility with 12 foot vertical banks. When a storm event occurred, the resulting high volume of water would sweep sediment downstream causing the banks to erode excessively. A lack of riparian and stream bank vegetation contributed to the erosion as well. The causes of the channel degradation appear to have originated from long term stream flow and watershed land use changes associated with increasing impervious surfaces, lack of riparian buffers, and increased frequencies in storm events. Due to these unstable conditions, the landowner had previously lost approximately 40 feet of property over the past several years. Restoration practices for this project included realigning the stream to a more stable planform, installing stabilization measures, providing a bankfull bench to alleviate velocities from higher flows during storm events, and using bioengineering practices. Woody riffles were installed to stabilize the channel bed, and, to stabilize the banks, toewood was installed along the outside meanders. Toewood not only adds roughness to the stream bank and reduces stream velocities, but it also creates habitat for in-stream wildlife. Bioengineering practices included the use of coir matting, warm season grasses, and live stakes. These practices shade the stream, which in turn create cooler water temperatures that are ideal for trout. Bankfull benches were also constructed to encourage the stream to dissipate its energy out of bank during storm events. Funding for this project, secured through the Maryland Department of Natural Resources Chesapeake and Atlantic Coastal Bays Trust Fund, was divided in two separate phases. The design portion of the restoration was completed in September of 2016 and implementation was completed in October of 2016. |
Existing conditions at the Western Run Stream Restoration with 12 foot vertical banks resulting in property loss and extreme erodibility along the stream banks.
During construction, the bank has been graded back and toewood has been installed along the meanders to provide stability and create habitat for in-stream wildlife.
Post construction, the site has been planted to establish vegetation growth. Toewood and riffles were installed. The design promotes out of bank floodplain connectivity during high flow events.
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