On Sept. 26, the Washington State Court of Appeals ruled that Clark County was not adequately meeting its National Pollutant Discharge Elimination System (NPDES) permit. This case was an appeal of an earlier 2011 ruling by the Washington Pollution Control Hearings Board (PCHB).

Under the Washington state permitting system, permitees are required to reduce stormwater runoff from new development to historic levels. A permitee can adopt an alternative stormwater management program as long as it provides equal or greater protection. In an agreement with the Washington State Department of Ecology, the county required developers to mitigate increased flow caused by the development itself. However, the county would reach historic runoff levels by managing stormwater offsite.

In 2011, PCHB ruled that the alternative program did not provide sufficient water quality protection, because the rule unlawfully exempted developments approved before the new stormwater rule took effect — a legal provision known as “vesting.” PCHB also ruled that the program unlawfully failed to require low-impact development at new development sites. Read more.