Stream Restoration and Soil Restoration cont.

The Lakeview Project. The South Fork of Beargrass Creek is an urban stream that has been eroding for decades. Typical of urban streams, it was straightened and channelized through a series of projects that date back to the 1920s. The project limits are located within a gentle bend of the South Fork. Streambanks throughout the project reach had eroded until the stream was encroaching upon several units of an adjacent condominium complex and residential properties across the creek from them.

The Lakeview project's purpose was to protect properties along the creek by controlling streambank erosion, enhance the riparian vegetation corridor, and reduce maintenance costs. Disturbances were limited to a narrow corridor along the stream within the existing sanitary and drainage easement. With this constraint, a complete stream restoration was not feasible. Thus, soil bioengineering techniques were used to stabilize the stream banks where they stood.

Nearly 300 ft of the channel reach was stabilized using a combination of soil bioengineering treatments and rock toe protection. Rock toe protection was installed just below the normal water level in the stream. Soil bioengineering treatments included live branch layering (constructing the streambank using alternating layers of live branches and compacted soil) and live fascines (tied bundles of live branches partially buried and staked in place along the streambank). Live branch layers were placed above the rock toe installation up to the bankfull elevation of the channel. Soil between branch layering installations was wrapped in biodegradable erosion control fabric to protect the soil until vegetation was established. Live fascines were placed at the bankfull elevation.

The Winding Falls Project. The Winding Falls project was constructed as part of the Winding Falls Sanitary Sewers and Force Main Project. A service road to the proposed pump station had to be built close to a bend in Longview Creek. MSD was concerned that severe erosion in the creek bend would wash out the new service road.

Construction of root wad revetment at Winding Falls.

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