AN INNOVATIVE APPROACH TO REUSE AND RETAIN DREDGED SEDIMENT FOR EROSION CONTROL USING GEOTEXTILE CONTAINERS IN ECOSYSTEM RESTORATION

摘要

Geotextile containers are used in construction of the U.S. Army Corps of Engineers' Peoria Riverfront Ecosystem Development Project in Peoria Illinois. Illinois River basin's ecosystem restoration was achieved with construction of 21-acre Mid-sized Island with associated dredging, channel excavation to create an aquatic habitat and restore deep-water fisheries habitat that has been lost in Lower Peoria Lake due to sedimentation. Three rows of geotextile containers with 100 ft long, 45ft in circumference and approximately 6ft high when filled are being used to create the island's structural embankment. Stage one was completed in early 2010 and employed approximately 165 geotextile containers. Bank stabilization would provide protection for approximately 80% of the hydrograph. Riprap would be placed after the completion of island construction until anticipated island slope erosion occurs at an unstable angle providing cost savings. Innovative method applied during construction by combination of both land-based and floating plant equipment used in dredging sediment; filtering and reuse of dredged sediment by pumping into the geotextile containers provided an environment friendly and efficient construction technique for establishing an island in lake with soft clay sediments & shallow waters. Mechanical dredging adjacent soft sediments was used to maintain high solid content with 40 percent liquid for pumping into geotextile containers thereby reducing turbidity and minimizing habitat issues.