Bioengineering for Land Stabilization

A large number of slopes and embankments throughout Ohio are experiencing shallow slope failures and/or erosion problems. The aim of this study is to identify bioengineering methods to address the Ohio Department of Transportation’s (ODOT’s) slope stabilization needs in response to these occurrences. Bioengineering is an ecologically, and often economically, attractive alternative to conventional slope stabilization techniques. The objectives of this research are: 1) to identify important factors that control success or failure of bioengineering methods, 2) to develop installation techniques and designs for successful application of bioengineering methods, and 3) to provide thorough documentation to aid in the development of future design guides for bioengineering work for ODOT. Three field installations were conducted and monitored at demonstration sites located in Muskingum, Logan and Union Counties. Results indicate that biostabilization methods can be effective for the stabilization of shallow (less than 3 – 4 ft.) slides if vegetation can be established. Establishment of vegetation is dependent on local soil and climate conditions, especially during the first growing season after installation. The use of instrumentation (tensiometers, piezometers) can be effective in predicting vegetation survivability. Side-by-side panel comparisons indicated that varying installation techniques do not affect the survivability of live willow poles. The cost of bioengineering stabilization, if properly planned and implemented, is expected to be approximately 25% less than that of conventional methods.