Guidance
Below are guidance documents, legislation links, and permitting information to guide CDOT staff and consultants through transportation project delivery and aquatic resource protection.
CDOT Guidance and Procedures
CDOT Wetland Program Cheat Sheet
Programmatic Wetland Finding Approval Memorandum of Agreement, 2024
Programmatic Wetland Finding Template (REQUIRED)
NEPA / 404 Merger Process and Agreement for Transportation Projects (2025 revision coming soon)
FHWA Regulation and Guidance
Executive Order 11990 - Protection of Wetlands
Technical Advisory T6640.8A - Federal Highway Administration Guidance for Preparing and Processing Environmental and Section 4(f) Documents (link takes you to the wetland part)
U.S. Army Corps of Engineers Regulation and Guidance
On September 8, 2023, the Environmental Protection Agency (EPA) and the Army Corps of Engineers published the new rule Revised Definition of ‘‘Waters of the United States’’; Conforming. The "Conforming Rule" amends the January 2023 Rule conforming it to the decision in Sackett vs. EPA. The Sackett decision holds that waters of the U.S includes only those “wetlands with a continuous surface connection to bodies that are ‘waters of the United States’ in their own right,” so that they are “as a practical matter indistinguishable from waters of the United States.” As a result, to assert Clean Water Act jurisdiction over an adjacent wetland a party now must establish:
1. The adjacent body of water is relatively permanent and connected to traditional interstate navigable waters, and
2. The wetland has a continuous surface connection with that relatively permanent water, making it difficult to determine where the ‘water’ ends and the ‘wetland’ begins.
Clean Water Act
The Clean Water Act establishes the basic structure for regulating discharges of pollutants into certain wetlands and streams and regulating quality standards for surface waters. The EPA provides a summary of the Act and links to more resources.
Section 404 Nationwide Permits
- Final Rule - December 2021 Reissuance and Modification of 41 Nationwide Permits
- Final Rule - January 2021 Reissuance of Certain Nationwide Permits
- 2021 Nationwide Permits Summary Table
- Regional Conditions for all 2021 Nationwide Permits in Colorado
Regional General Permits
- RGP 5 - Ditch-related Activities in Colorado (4 related documents)
- RGP 12 Extension - Aquatic Habitat Improvement for Stream Channels in CO
- RGP 37 - Stream Stabilization Projects in Colorado
- RGP 96 - Natural Disaster Mitigation & Flood-Related Activities
- Pre-construction notification form used for RGPs
Mitigation and Monitoring
- 40 CFR Part 230 - Compensatory Mitigation for Losses of Aquatic Resources; 2008 Final Rule
- Minimum Standards For Acceptance of Aquatic Resource Delineation Reports - Sacramento District, January 2016
- Regional Compensatory Mitigation and Monitoring Guidelines - South Pacific Division, 2015
- Regulatory Guidance Letter No. 08-03, Minimum Monitoring Requirements for Compensatory Mitigation
Clean Water Act Exemptions
Ditch Exemption Memorandum
On July 24, 2020, the U.S. Army Corps of Engineers and U.S. Environmental Protection Agency issued a memorandum to the field regarding application of the exemptions under section 404(f) of the Clean Water Act for the construction or maintenance of irrigation ditches and for the maintenance of drainage ditches.
Maintenance Exemption
Certain discharges for the maintenance, including emergency reconstruction of recently damaged parts, of currently serviceable structures such as riprap, bridge abutments or approaches, and transportation structures are exempt from the requirements under section 404 of the Clean Water Act.
Colorado Department of Public Health and Environment
House Bill (HB) 24-1379 directs the Water Quality Control Division to implement a dredge and fill authorization program and the Water Quality Control Commission to promulgate rules for individual permitting and mitigation by Dec. 31, 2025.
As of Jan. 1, 2025, any person seeking authorization to discharge dredged or fill material into state waters that are not subject to federal jurisdiction shall apply for a temporary authorization from the division. Temporary authorizations recognize nationwide (NWP) and regional general permits (RGP) issued by the US Army Corps of Engineers as valid authorizations to discharge dredged or fill material into state waters.
