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Stormwater Discharges from Construction Activities in Region 10


For general questions about the Construction General Permit in EPA's Region 10, contact:

In Region 10, EPA is the NPDES permitting authority for facilities in Idaho; facilities on Indian Country lands in Oregon and Washington; federal operators in Washington; and the Metlakatla Reservation and Denali National Park in Alaska.

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How Do I Get Coverage Under the CGP?

Do I Need a Permit?

Use this chart to help you decide whether you need to apply for coverage under the under the Construction General Permit (CGP): Construction General Permit Flow Chart

How to Apply

  1. Read EPA's 2017 Construction General Permit.
  2. Develop a Stormwater Pollution Prevention Plan (SWPPP) for your construction site.
  3. Complete an endangered species determination for the project site (details are noted in the CGP).
  4. Get authorization from EPA if you plan to use chemical treatment (most projects do not - see below for more information).
  5. File a Notice Of Intent (NOI) using EPA's NPDES eReporting Tool (CGP-Net).
  6. Implement the Best Management Practices (BMPs) outlined in the SWPPP.

Special Instructions for Chemical Treatment

If you plan to use cationic chemicals, you will need to get prior authorization from EPA's Regional Office. The following documents will help you compile the information we need to review your cationic chemical application.

Forms and Templates

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Permit Guidance

General Guidance



Construction projects in Idaho must apply for coverage under EPA’s Construction General Permit. Note that Idaho has added state-specific provisions to the permit. Please be sure to read section 9.7.1 of the permit.

Related resources:


The EPA CGP only applies to projects on tribal lands within Oregon. All other projects are within the State of Oregon’s permit program.


Projects operated by federal agencies in Washington must apply for coverage under EPA’s Construction General Permit.

Projects operated by state or private entities must apply for coverage under Washington’s Construction Stormwater General PermitExit(including projects on federal lands).

Related resources:

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