Colorado water law is famously known for its strict adherence to the prior appropriation regime that governs much of the American West. So much so, in fact, it even has its own colloquialism: the “Colorado Doctrine.” Certainly, at face value, it is a rigid system, built around seniority and curtailment to junior users.
But beneath all the surficial rigidity is a water regime surprisingly ripe with flexibility.
That flexibility is on full display this summer, when the Colorado Division of Water Resources (DWR) approved an emergency substitute water supply plan (SWSP) from the Colorado River Water Conservation District (River District) providing welcome relief to municipal water providers across all of Water Division No. 5.
A Historic Drought Tests Water Division No. 5
As of springtime this year, the 2026 water year is on pace to be one of the hottest and driest on record for the Upper Colorado River watershed. Peak snowpack arrived a month early and at about half of typical levels, with many stations recording their lowest readings on record. Several municipal providers have imposed drought restrictions, and some irrigation companies cut allocations to as low as 50 percent—conditions expected to be worse than even 2002, long the benchmark for a bad West Slope water year.
That poor hydrology meant a serious stress test for several integral components of the Upper Colorado River’s administrative regime. Green Mountain Reservoir (GMR), operated by the U.S. Bureau of Reclamation to supply compensatory water for West Slope uses, was not expected to fill, resulting in a threatened call against beneficiaries of the 66,000 acre-foot (AF) Historic Users Pool (HUP), many of whom have never faced curtailment. Similarly, there are numerous augmentation plans that rely solely on a GMR contract for water releases to replace downstream depletions. Separately, the calls at the Shoshone Power Plant in Glenwood Canyon and Grand Valley Canal (aka the “Cameo Call”) just outside Grand Junction started earlier and are expected to run longer than historically—it is anticipated these calls will be on for the entire irrigation season. Many decreed augmentation plans in Water Division No. 5 were not built to replace depletions that early, so the June call created a crisis for numerous small water users. The general inability for drinking water providers to operate outside their augmentation decree conditions when there is no available GMR water threatened public water deliveries and basic health and safety for thousands of residents.
Cue the Emergency SWSP
SWSPs are authorized under C.R.S. § 37-92-308. The statute was adopted after several Colorado Supreme Court decisions in the early 2000s involving the authority of the State Engineer to administratively authorize diversions without a water court decree. See Empire Lodge v. Moyer, 39 P.3d 1139 (Colo. 2001); Simpson v. Bijou Irrigation Co., 69 P.3d 50 (Colo. 2003). Under the SWSP statute, a water user can obtain annual administrative approvals to operate an augmentation plan or a water right transfer during the pendency of the Water Court case in which the out of priority ground water pumping or change of water right is being considered by the Water Court. The General Assembly also provided a pathway for an “emergency” SWSP, which also operates on an annual basis but is limited to no more than four renewals. An emergency SWSP, unlike a standard SWSP, which requires public notice and a longer timeline, may be approved without prior notice to address a public health or safety emergency. See generally C.R.S. §§ 37-92-308(6), (7). The River District’s proactive May 29, 2026 submission of the emergency SWSP allowed DWR to approve the plan on an expedited basis and cover the stressor months of June 1-August 31 (the 91-day statutory maximum). C.R.S. § 37-92-308(7).
The plan authorized the River District to augment out-of-priority depletions tied to municipal and domestic drinking water (paired with a requested one-day-per-week outdoor watering limit) located in any of the drainages of the Colorado River upstream from Palisade. The covered water provider entities are: (1) HUP beneficiaries lacking a functioning augmentation plan; (2) decreed plans relying solely on an unfulfilled GMR contract; and (3) decreed augmentation plans that do not contemplate replacing depletions during a full month of June administration. This includes everyone from towns to homeowners’ associations to water and sanitation districts. DWR estimated total qualifying depletions of 1,857 AF over the three months, driven largely by 837 AF of depletions in June alone. To cover them, the River District released (and continues to release) water from four sources it owns, contracts for, or is securing by agreement: Wolford Mountain, Ruedi, and Granby Reservoirs, and the Grizzly Reservoir/Independence Pass Transmountain Diversion System.
Consistent with the statute, DWR’s approval of the emergency SWSP includes specific conditions to protect other decreed water uses. Among other things, coverage was limited to depletions not subject to a local tributary call, transit losses are assessed, and approval comes with accounting and reporting requirements, including different depletion factors for different water users. Currently, the authors understand the River District is preparing an additional SWSP to release additional wet water for September and October, as limited summer monsoons have not changed the upper Colorado River hydrology.
Why the Emergency SWSP and 2026 Water Year Matter
For thousands of West Slope households, the River District’s emergency SWSP was the difference between turning on the tap and drawing a dry bath. Some small users with impacted augmentation plans did not even know the emergency plan was implemented to assist them. It also shows how the Colorado Doctrine, for all its rigidity, can quickly respond to emergencies. Nevertheless, because the plan currently runs only through August 31, affected water users should determine the legal availability of their water supply once the month ends.
For questions regarding SWSPs generally, or the end of the River District’s emergency SWSP, please contact:
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