Geocell wall and channel protection for U.S. Army Corps Flood Control Project

摘要

The Molly Ann's Brook Flood Protection Project is located in Paterson, Haledon, and Prospect Park, New Jersey. The brook is a tributary of the Passaic River and flows through an urban area. Communities along the 2.5 mile stretch of the brook have been subject to repetitive flooding due to inadequate channel capacity. The project was designed and constructed by the U.S. Army Corps of Engineers, Philadelphia District. The deeper and wider channel provides complete protection from flooding up to a 50-year event. The channel varies throughout the project from a trapezoidal riprap section to a rectangular section formed by precast concrete walls. Walls were required due to limited space and proximity of structures along the brook. In two areas the Corps opted to utilize innovative alternatives to the conventional riprap, gabions, and concrete retaining walls. The first alternate, the Presto perforated Geoweb Cellular Confinement System, also named a geocell system, was used to construct a 14 foot high, 400 foot long gravity wall. This wall was used to replace a more expensive reinforced concrete retaining wall. The design and construction phases were complicated by an undulating bedrock surface. The aesthetics and environment were improved by using tan colored material on the face of the first exposed cell and planting vines in the cell. The use of the geocell wall in a flood protection project was unprecedented for the Corps of Engineers. The second alternate was a single 4 inch layer of perforated geocell filled with low slump concrete. It was used to replace a 54 inch thick riprap layer, which was necessary due to high flow velocities and shear stresses at a critical bend in the brook. The use of the geocell system saved over 80,000 dollar in the two areas.