Instream Flow Rules Revisions to Implement House Bill 20-1157

The Colorado Water Conservation Board (CWCB) staff has drafted proposed revisions to the Rules Concerning Colorado's Instream Flow and Natural Lake Level Program (ISF Rules). The revisions to the ISF Rules will: (1) address the rulemaking requirements of HB20-1157; (2) update a reference to the CWCB's website; and (3) update references to Colorado Parks and Wildlife.

Staff held two informal stakeholder meetings on August 3 and August 18 to discuss the draft ISF Rules revisions. 

Staff invites interested parties to submit written comments on the draft ISF Rules revisions (third version of the draft) via email to Note that any comments received will be posted on the CWCB website (below). 

At the September 2020 Board Meeting, staff will ask the Board for authorization to initiate the formal rulemaking process and will review the proposed revised ISF Rules and the draft Statement of Basis and Purpose. For more information, contact Linda Bassi at or (303) 866-3441 ext 3204.