The SWaMP (Saugahatchee Watershed Management Plan) Project and Alabama Water Watch were extremely pleased to have Marlon Cook, Director, Groundwater Assessment Program, Geological Survey of Alabama, present results from a six-year GSA study, ANALYSIS OF SEDIMENT LOADING RATES AND IMPACTS OF UPPAVED ROADS ON SELECTED TRIBUTARIES TO GANT AND POINT A LAKES, COVINGTON COUNTY ALABAMA 2002-2007. The presentation was at Upchurch Hall on the Auburn University campus on December 16th, 2009.
Mr. Cook touched on erosion/sedimentation processes, and their affects on streams in Alabama. He showed results of the impressive study conducted by the GSA in Covington County, where GSA scientists measured sediment load in several streams before and after installation of BMPs (best management practices) on dirt roads that crossed the local streams.
The BMPs included chip-seal (surfacing with tar and limestone) of the road surface from hilltop to hilltop on both sides of a bridge, armoring drainage ditches along the sides of the road with limestone rip-rap, installation of curb and gutters, planting of vegetative cover on road sides, and check-dam installation in roadside ditches. Mr. Cook emphasized that a relatively small amount of road improvement on unpaved roads can make a dramatic improvement in stream water quality (manifest as reduction of dirt being washed into the stream during rain events) if the improvements are targeted to areas of high erosion at stream crossings. Results of the GSA study indicated reductions from 46% to 99% in sediment loads in streams, depending on the BMP treatments installed. The seminar closed with a stimulating discussion about things that could be done on Lee County’s 187 miles of unpaved roads to reduce the amount of dirt flushed into our local streams and improve their water quality.
SWaMP is administered and coordinated by Alabama Water Watch and Auburn University Fisheries Department, and partially funded by the Alabama Department of Environmental Management through a Clean Water Act Section 319(h) nonpoint source grant provided by the U.S. Environmental Protection Agency-Region 4.
Special thanks to Mr. Marlon Cook for traveling to Auburn University and sharing his knowledge and experiences with us in an effort to restore and preserve Auburn’s natural resources!