StormFilter cartridges filled with zeolite, perlite and granular activated carbon media remove total suspended solids and other pollutants.
Click here to enlarge imageAccording to Bill Reilly, Bellingham’s surface and stormwater utility manager, in 1990 the Department of Ecology selected Bellingham as one of the cities that it wanted to work with to improve water quality. About that time, several of the outfalls from Lake Whatcom were shown to be contributing pollutants; and the lake became the primary focus for improving water quality. As a result of these concerns the city created a limited utility, the Storm and Surface Water Utility (SSWU), to collect fees from development. These fees were used to begin requirements for development controls and to fund the Watershed Master Plan for the city.
While this was a start, additional funding was necessary to meet increasing regulations and provide adequate capital and operation/maintenance plans. In 2001, the city allowed the SSWU to add a monthly fee for property owners.
Bellingham’s watershed planners understood that pollution from urban areas is the most complex and difficult kind to control. They were particularly concerned with the Lake Whatcom watershed found directly east of Bellingham and covering about 37,000 acres. Forestlands cover 70 percent of the multiple use watershed. The lake provides drinking water and recreational uses, including boating, swimming, fishing and other activities. The city found that many of its existing stormwater systems around Lake Whatcom predated existing design and installation requirements and so did not meet current design standards.
Like many Washington communities, Bellingham has experience significant construction and development in the past several years. The clearing of land for buildings, parking lots, and landscaped areas has occurred at a rapid rate that forever changed drainage patterns. Rainfall from these surfaces runs quickly and directly into the areas streams, dramatically increasing their volume and peak flows.
The region’s rainfall intensity varies dramatically, affecting runoff rates. Depending on pollutant concentrations, the time between storms and the volume of rain, runoff carries sediment and pollutants away at different rates. And so the pollution and sediment content of stormwater varies markedly from location to location and from storm to storm.
This makes it important to manage the stormwater runoff from both large and small storms, not only for flood control, but also to preserve a high-level of water quality. Just a small amount of stormwater runoff can carry large amounts of soil and pollutants. That’s why, according to Reilly, the city looks at its projects annually to decide if any public construction work should include retrofits of its stormwater systems.