Workers have begun creating 36 curbside rain gardens in downtown Bellingham to cleanse runoff from 90 urban acres that drain into Whatcom Creek.
A $600,000 grant from the Washington Department of Ecology is paying for the stormwater portion of the project. In recent years, the agency has shifted its focus for dealing with runoff from expensive treatment facilities to so-called "low-impact development" methods, including rain gardens, green roofs, swales and pervious paving.
Bellingham already has several rain gardens, including ones at Cornwall Avenue and Maple Street.
Rain gardens capture, cool and cleanse runoff, and allow it to infiltrate the soil. Without them, dirtier and warmer stormwater flows into Whatcom Creek, which has problems with high temperatures and high fecal coliform levels, said Freeman Anthony, project engineer on the rain gardens for Bellingham's Public Works Department.
The downtown area where the gardens will be located is bounded roughly by Whatcom Creek on the north, Ellis Street on the east, Holly Street on the south, and parts of Garden, Magnolia and Commercial streets on the west.
Most of the rain gardens will be near street corners, on downslopes with existing catch basins to handle overflow. The gardens will be installed in the parking strip, with protective curbing on the traffic side, and will measure about seven feet wide and 10 to 20 feet long.
Perhaps 10 or more parking spaces will be removed to make room for the rain gardens, Anthony said. The loss of parking was one of several factors considered when choosing the locations, and several locations were changed after adjacent businesses expressed concern, he said.
In some cases, pedestrian improvements, notably bulbed-out intersections, will be installed along with the rain gardens. The gardens will be filled with drought-tolerant plants no taller than two feet.
For details about the downtown rain gardens, go to the City of Bellingham website, cob.org, and search for "Downtown Improvement Gardens."