Soil Bioengineering Stabilization of an Eroding Streambank along a Sanitary Landfill, Mill Creek, Cincinnati, Ohio

The Center Hill Landfill was owned and operated by the City of Cincinnati, Ohio for landfill of residential, construction and industrial waste from 1955 until its closure in 1977. A compacted soil cap 0.6 to 1.2 m (2 to 4 feet) thick was added after closure. The Landfill is located along Mill Creek on the outside bend of a slight meander. Two gravel-filled trenches were installed along the streambank to intercept leachate from the landfill. Significant erosion on the Creek's banks along the Landfill began to be noticed in the 1990s, threatening to uncover the leachate collection system and buried waste. The City treated the eroded by placing riprap on 100m long section by 3m up the bank (320 ft x 10 ft) of the toe of bank in July 1997; additional riprap was placed to the top of bank over a 12m (40 ft) section in February 1998. As erosion at the top of bank continued to worsen the City of Cincinnati's Office of Environmental Management (OEM) realized a comprehensive bank stabilization solution was needed. The OEM desired a bioengineering-based solution because, in addition to being cost effective and structurally sound, it would provide benefits of wildlife habit and aesthetic value that a conventional riprap treatment would not. The City hired The Bioengineering Group, Inc. as the design consultant, a firm that specializes in bioengineering-based solutions for streambank stabilization.