Evaluation of the Washington State Department of Transportation stormwater monitoring and effectiveness program for 2014–19

The U.S. Geological Survey was asked by the Washington State Department of Transportation to provide technical assistance as a third-party reviewer of their stormwater effectiveness monitoring program during the transition between the completion of the 2014 Washington State Department of Ecology permit requirements and start of the new 2019 Washington State Department of Ecology permit requirements. For the purposes of this evaluation, the U.S. Geological Survey reviewed Washington State Department of Transportation’s 2014 National Pollution Discharge Elimination System permit. This review focuses on sections S7, S8, G9, and appendix 4 of the permit that are specific to monitoring. These sections cover the methods of monitoring, the constituents that were monitored, laboratory requirements, reporting requirements, and data archival. Next, all quality-assurance project plans for the 2014 general permit and annual reports required for the permit were reviewed. The quality-assurance project plans and annual reports were reviewed to ensure that monitoring was executed and reported as required by the 2014 general permit. The monitoring requirements put forth from the permits were fully addressed in quality-assurance project plans and were completed and presented in the annual monitoring reports. Overall, the Washington State Department of Transportation monitoring program does not change much under its new 2019 permit. The Washington State Department of Transportation has followed through with the plan set out in each of its approved quality-assurance project plans and therefore, is in a good position to meet or exceed the new permit requirements in the upcoming 5-year permit cycle.