Permanent Water Quality (PWQ)

MS4 PWQ Program Overview

CDOT's Permanent Water Quality (PWQ) program is required under CDOT's Municipal Separate Storm Sewer System Permit (MS4).

Each CDOT region is responsible for evaluating new construction and redevelopment sites in the CDOT MS4 permit area to determine if stormwater controls are required. These controls are referred to as permanent water quality control measures (PWQ CM) or permanent best management practices (BMP).

For program assistance, consult region water pollution control managers/water quality specialists (see region contacts), or contact Program Manager Rachel Hansgen at [email protected] or (303) 757-9975.

CDOT Applications for Mitigation Pool Funding
Limited Funding Available - Contact Pool Fund Manager
This section applies to CDOT-advertised projects only.  For local agency-advertised projects seeking mitigation pool funding , please visit the PWQ Local Agency Call for Projects site.

Contact: Rachel Hansgen, Permanent Water Quality & Mitigation Pool Fund Mgr, 303-757-9975, [email protected] 

Application Materials

Limited Funding Available - Contact Pool Fund Manager

You must submit the following materials for all projects when applying for funding.

CDOT Mitigation Pool Fund Resources

Limited Funding Available - Contact Pool Fund Manager

    • Blank Permanent Water Quality Geodatabase
      Approved projects will submit a populated geodatabase prior to final acceptance of the PWQ project. The database is used to update PWQ CM inventory in GIS.
    • Permanent Water Quality Section of the Drainage Design Manual
      PWQ CM must meet one of three MS4 Permit design standards: Water Quality Capture Volume (WQCV), Runoff Reduction (Infiltration), or 80% TSS Removal.
      Proprietary structures must be approved by the New Jersey Corporation for Advanced Technology or the Washington State Department of Ecology, TAPE programs.
    • Permanent Water Quality Long Range Plan – identifies statewide plan for treating all stormwater runoff from CDOT's MS4 permit area.
    • Permanent Water Quality Program Manual
      This document provides criteria for determining when PWQ CM is required and information about applying for mitigation pool funding.
    • Colorado Senate Bill 15-212 – stormwater detention and water rights
    • Design Bulletin 2015-6: PWQ Mitigation Pool
      This 2015 document describes tracking mitigation pool fund money after disbursement to approved projects.