Glenwood looks to boost river’s quality
December 14, 2006
Aspen, CO ColoradoGLENWOOD SPRINGS The Gold Medal waters of the Roaring Fork River will get a boost this week when Glenwood Springs installs a stormwater runoff trap on one of its largest water drains.Assistant city engineer King Lloyd won a $7,200 grant from the Colorado River Water Conservation District for a sediment and pollutant trap retrofitted to one of the city’s largest stormwater drains, a 36-inch pipe that carries the collected water from a 165-acre area downtown.Lloyd thought of the idea when he heard the results of the Roaring Fork Conservancy’s “Stormwater Assessment and Education Report,” presented to the Glenwood Springs City Council last year. “The report brought to light a lot of things that existed in town,” he said, some of which needed changing.Stormwater is considered one of the primary sources of potential pollution to the Roaring Fork River, according to the Conservancy. Rainstorms carry pollutants such as trash, hydrocarbons from gasoline, sediment and fertilizer from lawns, golf courses and ranches into a water system.”The rule of thumb is the first half-inch of rain is the primary carrier of all that nasty stuff,” he said.As a result of the study, City Council requires all new developments to mitigate stormwater runoff before it reaches a water course. “It is also standard procedure that any reconstruction of city streets that have a drainage system will be upgraded to ensure that stormwater quality is improved,” Lloyd said.In 2005, Lloyd applied for and won the grant from the river district for a trap that could be installed in existing drain pipes in the city to filter out sediment, trash and hydrocarbons. Then he had to come up with a detailed design and bid it out to a contractor. Becvarik Brothers of Glenwood Springs won the contract for $39,000.This week Becvarik and city crews will install a large chamber in a cutout section of the drainpipe. Another 10-inch pipe outlet will be added “to intercept the first flush” of stormwater at a lower elevation than the big pipe. A “snout” or trap will be installed over both pipes that will maintain the level of water inside the chamber and trap the floating trash and hydrocarbons. Sediment will settle to the bottom of the chamber.The cleaned water will go out through the 10-inch pipe, flow across city property below the high school and percolate into the gravel beds alongside the river. In the event of a big storm, Lloyd said, the water will flow through the chamber to the 36-inch pipe and directly into the river as it does now.”It’s a pretty cost-effective way to deal with [stormwater],” Lloyd said.