Evaluation of Flared-End Inlet Protection Products for Sediment Retention

015877420197-91912016White PaperPDFTech ReportFHWA-ICT-16-004R27-102Construction sitesCulvert inletsErosion controlField testsGeotextilesPondingRunoffSedimentsWater quality managementDetention basinsConstructionEnvironmentHighwaysI15: EnvironmentI26: Water Run-off - Freeze-thawI50: Construction and Supervision of ConstructionUnited StatesIllinoisIllinois Center for TransportationBhattarai, RabinKalita, PrasantaAzeem, AnwarJha, RanjeetIllinois Center for TransportationUniversity of Illinois at Urbana-Champaign. Dept. of Agricultural and Biological EngineeringIllinois. Dept. of Transportation. Bureau of Materials and Physical ResearchUnited States. Federal Highway AdministrationUS Transportation CollectionConstruction sites are considered one of the main sources of sediment and contaminants that can create water quality concerns in the receiving waters. When rainfall occurs, loose soil particles are disintegrated and eroded from the bare soil area and transported to roads and parking lots. When earthwork is performed to construct buildings and highways, the rate of erosion increases. The sediment from these areas mixes with water and enters the roadside when it rains or snow melts. This can lead to clogging of drainage systems and street flooding. This can also escalate treatment cost due to increased sediment load for the wastewater treatment facilities. Various tests were performed to analyze the effectiveness of flared-end inlet protection products. The tests were conducted at the Erosion Control Research and Training Center (ECRTC) of the University of Illinois at Urbana-Champaign. These tests analyzed the ability of the products to prevent sediment from entering curb and gutter inlets via site runoff. The goal of these tests was to compare the various products and determine which would perform the best in preventing sediment from entering the inlets at construction sites. Several criteria were used in testing in order to make the best recommendations to the Illinois Department of Transportation (IDOT). The products analyzed in testing were (1) sediment log, (2) silt fence (with woven monofilament fabric), (3) silt fence (with IDOT-approved fabric), (4) straw bale, and (5) stone. The duration of the test was 30 minutes with a discharge rate of 158 gpm (10 L/s). One 5 gallon bucket of clay soil was initially mixed into a 300 gallon filled tank. Another 5 gallon bucket was later poured at 10 and 20 minutes. This mixture would spill over into the channel, where samples would be collected before and after the product was installed. The water samples were collected every 5 minutes and were oven-dried to determine sediment concentration. With this procedure, it was possible able to determine how efficient each product was in terms of sediment retention. It was found that the sediment log and silt fence with woven monofilament fabric performed better than the other products tested. Although several products were able to filter efficiently, they often created heavy amounts of ponding. The evaluation was based on two criteria: water should be able to infiltrate the product without creating heavy ponding and the product should retain a large fraction of the sediment75