MS4 Quality Assurance Monitoring Plan
The City of Portland recently updated the MS4 Quality Assurance Monitoring Plan in early 2015. The monitoring plan fulfills requirements of the city's National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) permit. The Oregon Department of Environmental Services (DEQ) issued the permit to the City on January 31, 2011, for a third permit term (through January 30, 2016).
The monitoring plan describes stormwater and surface water monitoring the city will conduct, including monitoring parameters, locations, and procedures. Monitoring data will be used to help evaluate and, if needed, modify the city's stormwater management program.