Construction Stormwater Permit

Information from the Washington state department of Ecology


  • Construction Stormwater General Permit - This statewide permit applies to activities conducting construction activities that discharge stormwater to a surface water body or to a storm sewer system that drains to a surface water body. 
  • Fact Sheet - This fact sheet is a companion document to the draft revised National Pollutant Discharge 5 Elimination System (NPDES) and State Waste Discharge General Permit for Stormwater 6 Discharges Associated with Construction Activity (Construction Stormwater General Permit, or 7 CSWGP). 
  • Focus on Construction Stormwater - Construction activities required to be covered by the CSWGP include land-disturbing activities such as clearing, grading, or excavating, that: Read More
  • Disturb one or more acres of land, or are "part of a larger, common plan of development or sale" that will ultimately disturb one or more acres of land, and that
  • Discharge stormwater from the site into surface water(s) of the state or into storm drainage systems that discharge to surface waters of the state.
  • Final Tier II Anti-degradation Plan - All applicants for coverage under the CSWGP have "the potential to cause a measurable change in the physical, chemical, or biological quality of a water body" and meet the definition of a "new or expanded action." Therefore, Ecology has prepared this Anti-degradation Plan during the 2010 CSWGP development process to comply with the Tier II anti-degradation rule (WAC 173-201A-320). Read More
  • How to Meet Ecology's Construction Stormwater General Permit Requirements: A Guide for Construction Sites - This guide provides an overview of the Construction Stormwater General Permit, including who needs a permit, permit requirements, and application information. Read More

  • Eastern Washington Erosion Prevention and Sediment Control Field Guide - This Field Guide provides a quick handy guide for individuals involved in land disturbing activities, such as clearing, grading, and/or excavation work. Homebuilders, general contractors, road builders, installers or best management practices (BMPs), planners, designers, plan reviewers, and inspectors will benefit from using this field guide.
  • Implementing Construction Site BMPs - The University of Montana has developed an on-line interactive guide and resource library to assist contractors with the installation, evaluation, and enhancement of construction stormwater BMPs. Although this tool is focused on projects in the Northern Rocky Mountains, it contains numerous graphics and photos of construction BMPs – both successful installations and improper installations.
  • Transfer of Coverage Construction Stormwater General Permit - This form transfers permit coverage from the original permittee to one or more new permit holders. Read More
  • Erosivity Waiver Certification - This form is used by construction site operators to request an exemption from the Construction Stormwater General Permit based on low erosivity during the period of construction activity. Read More


Frequently Asked Questions (FAQ) with answers about contaminated construction sites are available for your use on the Construction Stormwater General Permit (CSWGP) "Contaminated Water on Construction Sites" webpage. Follow this link


Stormwater Pollution Prevention Plan (SWPPP) template and a new Construction Stormwater Site Inspection Form template are available on the Construction Stormwater General Permit (CSWGP) website.

Follow this link to the CSWGP website:

The links are on the right side of the screen in the light blue ribbon.

Request for Chemical Treatment - Construction site permit holders use this form to request permission to use chemical treatment of construction stormwater runoff. Read More

Site Inspection Checklist - Read More

Construction Stormwater General Permit Application Form - This application form is for permit coverage under the Construction Stormwater General Permit. Read More

Permit Fee Activity Status Change Form - Use this form to reduce permit fees on inactive sites, or to notify Ecology that your site is now active. %3