12/7/09

Erosion control on Pheasant Branch Creek, Middleton WI

I'm reporting on Pheasant Branch because of the creative methods used there.  It shows that when a city works with a firm experienced in restoration, they have access to a bigger bag of tricks. 


One of the three largest tributaries to L. Mendota, Pheasant Branch has been undergoing streambank repairs to protect the lake's water quality.  View N from Century Av.

"Pheasant branch Conservancy is a refuge for many kinds of wildlife and is enjoyed by thousands of visitors each year. Along with this use, the City actively manages the corridor along Pheasant Branch Creek to balance public use, while improving wildlife habitat and water resources.

In the creek corridor between Century Avenue and Park Street, the City worked with JFNew, and ecological consulting firm based in Verona, who designed and installed stream bank restoration measures using large root wads placed along the outer meander bend of the stream to deflect flows away from the bank while increasing habitat. These measures have resulted in improved stream habitat and provide an example of biologically-friendly stream stabilization measures.


Root wads are the dark masses, partially buried in the riprap. They slow waters, increase wildlife habitat, and help increase the angle of riprap.

From July 27-July 30, 2009, the city continued its work to stabilize and restore the corridor along Pheasant branch Creek. This type of erosion control has been used successfully along Pheasant branch in the past to mitigate against the high peak flows caused by large volumes of storm water runoff from impervious areas in the watershed. The chosen stabilization techniques increase habitat complexity such as small spaces found within rootwad composites which provide cover for small fish, as well as reptiles and small mammals found in the riparian habitat.

These techniques add structural diversity to the stream creating a variety of micro-flow conditions, enhancing aquatic invertebrate diversity by allowing benthic organisms to select specific positions with the geometry of the local flow conditions.

The native seed mix (see JFNew Dry Sandy Slope Mix) planted on these sites is full of species endemic to southern Wisconsin with deep extensive rooting systems. Once established, the dense roots of these native grasses and forbs will trap and hold bank material in place, further reducing erosion of bank sediments while increasing the biotic diversity of the riparian corridor. Local residents, other municipalities, and agency staff have praised this work for its beneficial re-use of natural woody materials and its incorporation of habitat improvements.


Root wads stabilizing bank of Pheasant Branch

For more information on this project contact: Aaron Steber, Ecological Resource Specialist, JFNew , 608-848-1789, asteber@JFNew.com  "  The above text is quoted from a kiosk in the Conservancy.


Variety of techniques: revegetation, riprap, baskets of rock, & metal retaining walls.

Click here for a slide show of erosion control on Pheasant Branch Creek.

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