Wisconsin's Role in Great Lakes Restoration - American Water ...

SESSION 4B:
Watershed and Wetland Management
Friday, March 4, 2011
10:20 – 11:40 a.m.
Kinnickinnic River Flood Management and Watercourse Rehabilitation
Ryan P. Van Camp, Short Elliott Hendrickson, Inc. (SEH), Appleton, WI,
rvancamp@sehinc.com
Tom R. Sear, Short Elliott Hendrickson, Inc. (SEH), Milwaukee, WI, tsear@sehinc.com
Patrick C. Elliott, Milwaukee Metropolitan Sewerage District (MMSD), Milwaukee, WI,
pelliott@mmsd.com
The Kinnickinnic River watershed is an approximately 25 square mile, highly urbanized
drainage area, located in south central Milwaukee County and tributary to the Milwaukee
River Estuary. The Kinnickinnic River has undergone considerable alteration in the past,
including channel widening and realignment, and the installation of concrete lining along a
significant portion of its length. These channel modifications were completed to provide flood
management, and for a period of time reduced water surface elevations during periods of
intense rainfall. Continued urban development in the watershed, plus a recent pattern of more
frequent high intensity rainfall events, resulted in an unacceptable level of flood management
for the one-percent probability (100-year) design event along significant portions of the
watercourse. As a result, the Milwaukee Metropolitan Sewerage District (MMSD) initiated a
series of projects to provide enhanced flood management and watercourse rehabilitation
within the watershed.
Two final design and construction projects are currently being completed along a downstream
segment of the Kinnickinnic River as part of the initial efforts in the long term program. These
“early out” projects include replacing of the South 6th Street Bridge to expand the hydraulic
opening and rehabilitating approximately 1,000 feet of watercourse, located immediately
downstream. The upstream portion of the watercourse segment (500 feet) contains a
concrete lined channel confined by steep embankments and existing infrastructure. The
downstream portion of the watercourse segment (also 500 feet) contains an earthen/rock
lined channel, with a steep/failing south embankment. Watercourse rehabilitation
improvements include removing the concrete lined channel; developing a stone-lined main
channel, with riffle and pool sequences; salvaging and reusing on-site limestone blocks;
establishing stable embankment side slopes through the development of tiered retaining
walls, where necessary; developing a vegetated wetland floodplain and upslope vegetated
communities, using native plant species; and grading to allow the future development of an
important link within an urban bike trail.
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