Inlet and Storm Drain Protection Temporary and long-term defense BY CAROL BRZOZOWSKI I CITY OF TACOMA SOLID WASTE MANAGEMENT FACILITY n stormwater management for both temporary and post-construction measures, inlet and storm drain protection is one of the first lines of defense. It’s also a measure that often works in combi-nation with other best management practices (BMPs) as part of an overall erosion control or stormwater manage-ment program. Jim Nunn, facilities maintenance and repair supervisor for the city of Tacoma, WA, sought a solution to a sediment control challenge on the yard of the city’s solid waste recovery and transfer center. The site—a transfer station—is a former landfill, now capped. The city had constructed a new parking lot at the site in late 2014. “We had a trench drain in our parking lot,” says Nunn. “We had just installed a new parking lot out here for refuse trucks. The trench drain had a biomedia in it, and with the amount of sediment that was coming off the trucks, it was plugging up when we did get a heavy rain; we just got over-whelmed. We constantly had to clean that thing out. It just packed in there.” Because solid waste is constantly hauled in and out, “We have a huge amount of truck traffic, plus the customer traffic as it is a transfer station now,” says Nunn, adding that the activity generates significant sedi-ment and debris. The Northwest is also subject to a lot of heavy rain, Nunn points out. When the significant rain events occur, large amounts of sediment and debris have been washed into the large drains at the bottom of a slope at the east end of the parking area, clogging and compromis-ing the performance of the biofilters. The in-grate filtration that was being 48 EROSION CONTROL used slowed to a near stop, causing water runoff to flood back over the grate and into the yard. Nunn concluded that having to change the biomedia every time it was plugged would be a time-intensive task, thus calling for an alternative solution. Although he found no answers in examining the city’s stormwater pol-lution prevention plan (SWPPP), he received a sample of a Heavyweight DuraWattle from Chris Ott, the city’s senior environmental specialist. Heavyweight Sediment Control Solutions’s Heavyweight DuraWattle is a flexible sediment barrier designed to address the problems and failures of sediment control BMPs. Constructed from UV-resistant material, it can also withstand vehicle traffic and quickly rebound back to shape and can be applied on soil, sidewalks, or hard surfaces. According to Heavyweight Sediment Control Solutions, ASTM field tests demonstrate a 96.6% sediment reten-tion and 58% turbidity reduction. The DuraWattle is designed as a lightweight continuous barrier with interlocking ends. The wattle doesn’t absorb water or pollutants; water flows through it rather than ponding or back-ing up. The square profile design helps control dust. The wattle is reusable. Nunn was impressed with the wattle and decided it would address the challenge on the transfer station site. He favored its durability and that it was designed to be driven over by vehicular traffic. That was a sig-nificant factor, given the drains were located at the entrance of the parking lot and some 60 trucks drive over them several times a day. WWW.EROSIONCONTROL.COM DuraWattle stands up to vehicle traffic at a Tacoma transfer station.