Here at the Spokane Riverkeeper, we work to clean up and bring awareness to nonpoint source pollution. Nonpoint source pollution, as its name implies, comes from many diffuse sources. As rain or snowmelt runs over land it picks up pollutants and deposits them in our waters. Our water quality monitoring program aims to bring attention to and measure theses pollutants in our streams. On that note, check out how dirty Hangman Creek was this week (3/17/15)! 
However, cleaning up nonpoint source pollution falls to a variety of organizations which employ a variety of methods. The Washington State Department of Ecology (Ecology) is tasked with enforcing the environmental regulations in Washington State. Recently, we wrote a letter to Ecology, supporting the work they do. In short we said....
I want you to understand that much of the public that we represent stands with Ecology in their efforts to develop a non-point plan, establish the terms of compliance to this plan and we stand by the regulatory efforts of your ground teams to consistently hold parties accountable in protecting Washington’s public water resources.
Check out the entire letter: Ecology letter 3-19-15.
Enforcing existing laws provides a strong regulatory backbone which will drive all other pollution control efforts.