Public Notice: Draft Permit Actions, Enforcement Actions, and Other Documents

This is for the 14-day permit applicant review of preliminary drafts for individual Colorado Discharge System Permit (CDPS) permits that are new or being renewed. The public can review these documents, but they are subject to change, and the opportunity for public comment is when the Public Notice comment period starts at a later date.

APPLICANTS ONLY - Use this preliminary draft comment form to identify errors in the preliminary drafts on notice.

Instructions on how to use the template:

• Please email your completed public comments form as a Microsoft Word document to the permit writer. (listed in the table below).
• If you would like, please feel free to submit the comments as a PDF as well, but the division will use the Word document for our responses.
• If you would like the division to review additional reference documents, please describe and reference them in the public comment form.

Use this draft permit comment form for comments on  Colorado Discharge System Permit (CDPS) permits on notice.

*Please use this comment form for COD000000 General Authorization for Discharge of Dredged and Fill Materials Into Isolated State Waters.

Instructions on how to use the template:

• Please email your completed public comments form as a Microsoft Word document to the permit writer. (listed in the table below).
• If you would like, please feel free to submit the comments as a PDF as well but the division will use the Word document for our responses.
• If you would like the division to review additional reference documents, please describe and reference them in the public comment form.

WQCD invites you to review and comment on a number of draft actions under the Clean Water Act and the Colorado Water Quality Control Act, including draft permits, draft permit modifications, and settlements/penalty actions. Please go to here to review and comment on draft actions.

You usually have 30 days to make comments on the draft action but please check the exact deadline on the website. Comments may be emailed to the listed contact or mailed to:

         CDPHE, WQCD-P-B2 
         4300 Cherry Creek Drive South
         Denver, Colorado 80246-1530

Purpose of Public Notice: To solicit public comment on the proposed Compliance Order on Consent between the Division and Mountain Brook Partners, LLC. This compliance order resolves alleged violations of the Colorado Water Quality Control Act and Mountain Brook Partners, LLC’s discharge permit, as identified in Notice of Violation / Cease and Desist Order Number SO- 240206-1, issued on February 6, 2024. Mountain Brook Partners, LLC was responsible for construction activities at the Mountain Brook Partners project located in Boulder County, Colorado. Division Contact: William Everett, 303-692-2290 / william.everett@state.co.us

Documents related to the above enforcement actions are available for public inspection at the Division. Copies of the above actions are available upon written request to the Division. Public comments should be submitted by December 13, 2025 and directed to CDPHE, WQCD-CWE-B2, 4300 Cherry Creek Drive South, Denver, CO 80246-1530.

Draft 401 certifications for discharges from federal facilities

Under section 401 of the Clean Water Act a federal agency may not issue a permit or license to conduct any activity that may result in any discharge into federal waters in Colorado unless Colorado issues a Section 401 water quality certification.  These certifications may include additional permit conditions needed to protect Colorado waters.

EPA issues discharge permits for federal facilities in Colorado. Colorado has received EPA draft permits for the following activities and is requesting comment on draft certifications for these activities.

The methodology for developing numeric and narrative effluent limits are described in the permit fact sheet and, if applicable, the water quality assessment (WQA) which is typically an attachment to the fact sheet. Those documents reference relevant statues (e.g., Colorado Water Quality Control Act), regulations (e.g., Regulation 61 Colorado Discharge Permit System Regulations), and Water Quality Control Commission (WQCC) policies (e.g., Policy 20-1 Policy for Interpreting the Narrative Water Quality Standards for Per- and Polyfluoroalkyl Substances [PFAS]) which are available on this website.

In addition, the fact sheet or WQA may reference the Water Quality Control Division’s Clean Water policies, guidance, and memoranda of understanding that are available on this website.

To assist in the review of a specific permitting action, here is a link to a blank Permit Builder Tool (PBT). The division will be transitioning to this version in 2026 which has additional information to add the public’s review. The PBT for a specific permitting action may have started with the older version that lacks the additional information and has the earlier tabs in a slightly different order.
 

The sources and time frames of water quality, flow and effluent data used in the permit development process is detailed in the WQA. The water quality and effluent data is entered into the Permit Builder Tool (PBT) along with the results of flow calculations. Flow data is entered into spreadsheets to format for DFLOW or to calculate low flows for nutrients. The Division uses mostly publicly available ambient water quality data that can be found at the following site: Water Quality Data Portal. If non-publicly available data is used, then the source of the data will be detailed in the WQA, so the public can request it.

Here is a link for the DFLOW program executable, code description of modifications to make DFLOW consistent with Regulation 31, Appendix A, and operating instructions on formatting input files and running the program.