In late March, the Colorado Supreme Court ruled in County of Boulder v. Boulder & Weld County Ditch Co., 367 P.3d 1179 (Colo. 2016). While this case did not involve any novel questions of Colorado water law, it did provide a clear warning to applicants for changes of water rights that they must be prepared to demonstrate detailed evidence of historical beneficial use, even in very complicated situations, for their claims to be approved.

This case involved an application by Boulder County to change water rights from an irrigation ditch for use to augment groundwater depletions from gravel pit ponds to support an open space park development. The ditch at issue carried a very senior priority of 1861, and had been decreed to irrigate 120 acres. However, the original decree did not identify which 120 acres could be irrigated. The water right for the ditch had long since been divided into fractional ownership, quantified as 185 “inches” (a commonly used method to divide a flow rate into smaller interests). Boulder County owned 100 inches, and other owners held the remaining 85 inches.

The Division 1 Water Court denied Boulder County’s application, holding that the County failed to prove the extent of historical use of the water right. The water court also held that the County should have conducted a “ditch-wide” historical use analysis, rather than a parcel-specific analysis, because the County’s approach would have resulted in the County obtaining credit for almost all of the decreed water right, even though several other owners also owned fractional interests in water right.

In Colorado, water rights are decreed for specific places and purposes of use. If an owner of a water right wishes to change that water right for use at another location or for a different use, the applicant must apply for approval from the water court. In order to ensure that the water right is not enlarged to the detriment of other water users, the court will quantify the water right based on actual historical beneficial use. Often, this results in a significant reduction in the annual amount of a water right, from the original decreed limits. Therefore, applicants must conduct a detailed historical use analysis, in order to make their best case regarding the amount of the water right that should be carried forward for a new use. In some cases, it is very difficult to reconstruct the use of a water right over many past decades. Often, the original users of the water are no longer alive. Applicants must resort to field notes from state water administration officials, written statements from the former users, if they exist, aerial photographs, and interviews of neighboring landowners in order to reconstruct the historical use of the water as best they can.

The murky history of the water right at issue in Boulder County v. Boulder & Weld County Ditch Co. led to the water court’s denial of the application, and the Supreme Court affirmed that ruling. The applicant had not proven to the satisfaction of the court just how much of its water right had actually been used on one of the claimed places of use. Other water rights had also been used on that farm, and there was no direct evidence that this specific water right had actually been used there, even though it had been delivered to the landowner’s headgate. Also, the court was unconvinced that the County had not overestimated its historical use of the water right for a 22 year period, from 1950 to 1972. The court found that the historical water delivery records from 1973 to 2000 were accurately calculated, but that was not good enough. There were no delivery records for the earlier 22 year period, and the applicant was not entitled to an assumption that it had taken its full pro rata share of the water right during this period. Thus, the Supreme Court affirmed the water court’s denial of the County’s application to change the water right.

This case serves as a warning to anyone who would seek to change water rights with complicated historical use patterns to a new use. A detailed demonstration of actual historical beneficial use on specific land will be required, even if the available records are unclear. In order to protect other water users against injury due to a potential expansion of an existing water right, the court will err on the side of denying a change of use application, if it is not convinced that the new use will not be greater than the historical irrigation use. It is crucial that water right holders conduct a thorough and credible historical use analysis, and compile sufficient evidence to convince the court just how the water right had been used over time. Otherwise, applicants run the risk of expending very substantial resources and time in a change-of-use proceeding, and end up having their applications denied.

Welborn Sullivan Meck & Tooley’s water attorneys have significant experience successfully obtaining change of water right decrees for municipal, industrial, and other clients. If you are considering changing a water right to a new use, we would be happy to discuss your plans.