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December 31, 2019  |  Written by Leila C. Behnampour

Amendments Adopted to Colorado Ground Water Commission’s Designated Basin Rules

Water users and developers in Colorado’s Designated Ground Water Basins – take heed.  New amendments to administrative rules will significantly affect existing and future groundwater uses in eastern Colorado.  Impacts will cross into all user sectors, including agricultural, energy and development water uses in a designated basin.

Final Rule Amendments

In fall of 2019, the Colorado Ground Water Commission (Commission) adopted amendments to the Rules and Regulations for the Management and Control of Designated Ground Water, 2-CCR 410-1 (Designated Basin Rules or Rules).  The Designated Basin Rules are the substantive rules that govern designated groundwater management in Colorado’s designated basins, establish allowable depletion rates, and set the required standards to change designated groundwater rights.  These recent amendments added to earlier amendments to specific Designated Basin Rules concerning aquifer storage and recovery and replacement plans.  Both sets of amendments were comprehensive, covering nearly every rule, with the stated goal to make each rule effective, efficient and essential pursuant to the Colorado Governor’s directive.

The process to amend the Rules began in 2017 with stakeholder meetings, with formal initiation in 2018.  Many disputed issues were resolved in the stakeholder meetings, and the vast majority of the amendments were undisputed.  The Commission’s Hearing Officer held a hearing in 2019 to determine whether Commission staff (Staff) was reasonable in the development of the proposed rules and whether the agency exceeded its authority, or lacked a basis in the record for a rule.  The Hearing Officer found that Staff had not exceeded their authority, lacked a basis for the proposed rules, or recommended rules that were unreasonable, with the exception of proposed Rule 7.12.1.

Rule 7.12.1, Alternate Point of Diversion Wells and Supplemental Wells

For proposed Rule 7.12.1, which dictates alternate points of diversion and supplemental wells, the Staff proposal was not entirely accepted.  Staff’s proposed Rule 7.12.1 prohibited new well permits for alternate point of diversion wells and supplemental wells if the Ground Water Management District Rules prohibit them or if the aquifer was over-appropriated.  Staff argued that the proposed rule was within the Commission’s statutory authority and provided needed clarity.  Opposers argued that, by statute, the Legislature already addressed the issue by prohibiting supplemental or alternate point of diversion wells in areas in which the wells would deplete the aquifer in excess of the rate of depletion prescribed by the Commission or Ground Water Management District rules and regulations.  The opposers maintained that the proposed rule was overly restrictive and exceeded the Staff’s statutory authority.  The Hearing Officer agreed with the opposing parties, and concluded that Staff’s proposed rule invalidated the plain language of the statute, requiring deletion.  However, the Commission disagreed with the Hearing Officer and opposers, and adopted a modified version of proposed Rule 7.12.1.

The modified version of Rule 7.12.1 explains that the Staff may not approve a request for alternate point of diversion and supplemental well permits in any over-appropriated aquifer.   The rule provides that this prohibition is because the allowable net average annual depletion rate has already been exceeded such that the well would deplete the aquifer in excess of the rate of depletion prescribed by the Commission.

This rule change is significant.  For over-appropriated areas, the Rule’s application could result in denial of a supplemental or alternate point of diversion well permit.  The full text of Rule 7.12.1 and the final amended Rules are available here.

The amended Designated Basin Rules will be effective January 14, 2020.  Any person or agency adversely affected by a rule or rules has 35 days after the effective date of the amended Rules to lodge an appeal in district court.  The existing rules apply until January 14, 2020, including existing rules governing applications for alternate point of diversion and supplemental well permits.  Therefore, designated groundwater users may consider filing applications prior to January 14, 2020 to be able to take advantage of the existing rules.


If you are a water user in one of Colorado’s designated groundwater basins, and you are considering a change in use or diversion location for an existing well, a detailed analysis of the new amendments and potential pitfalls as they apply to your situation can ensure success of your application.  If Rule 7.12.1 may apply because the area is over-appropriated, then other solutions may be necessary.

For more information on the Colorado Ground Water Commission and the Designated Basin Rules, please contact Leila Behnampour at (303) 449-2834 or

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