Low Impact Development, or "LID", is a series of construction practices designed to mimic natural infiltration of stormwater on developed sites. These practices include rain gardens, narrow roads, pervious concrete, and vegetated roofs. Because LID promises to reduce traditional stormwater detention costs and allows homes to be marketed as "green", developers across the state have been incorporating LID into their projects. However, LID remains expensive and frustrating. The technology is still new, infiltrating soils are hard to find, long-term maintenance can be problemmatic, and most jurisdictions are slow to embrace--or even understand--LID.

Despite these problems, several Western Washington jurisdictions will be the first in the nation to have mandatory LID in their local codes. Last year, the Pollution Control Hearings Board issued decisions on appeals of the Department of Ecology's three municipal stormwater permits. For Phase I jurisdictions (Seattle, Tacoma, King, Pierce, Snohomish, and Clark), the Board held that construction projects must use LID "where feasible." The Board did not require LID in Western and Eastern Washington Phase II jurisdictions; however, it directed those jurisdictions to pave the way for LID. In response to the Board's decisions, Ecology revised the municipal permits (which dictate the content of local erosion ordinances) but left the details out. These details, including which LID practices will be used, what makes them "feasible," how well they must perform, and when they must be instituted by local governments, will be hammered out by two advisory committees--Technical and Implementation--created by Ecology. Ecology named BIAW to the Implementation Committee. BIAW will use its seat at the table to keep LID requirements grounded in reality--LID technology must be available and affordable, the market receptive, and local governments on board.

Coming Soon: LID Regulation Tracker

Find out the latest action by the Department of Ecology's Technical and Implementation Advisory Committees, Phase I and II municipal permit updates, and local code changes that will require new site practices.

Back to Legal Page