The Junior Well: Prior Appropriation, Augmentation Plans, and the Takings Argument
In 2015, Wes Corrigan drilled a 600-foot well on his 320-acre ranch in the Arkansas River basin to irrigate 90 acres of hay. The well has no court-approved plan for augmentation. In June 2024, the State Engineer's Division 2 office received a call from the Catlin Ditch Company, whose 1888 decree supplies senior irrigation rights. Division staff measured stream depletion and concluded that Corrigan's pumping depletes the Arkansas by 210 acre-feet per year, injuring Catlin. The Division issued a cease-and-desist order under C.R.S. § 37-92-502(2). Corrigan argues that (1) his use is beneficial and reasonable, (2) the well is on his own land and the ditch did not divert in dry years, so there was no real call, and (3) shutting him down is a taking. He asks whether he can keep pumping while he applies for a plan for augmentation.
1. Does Corrigan's beneficial use of the water protect him from Catlin's senior call? Explain the priority rule and the no-injury rule.
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No. Colorado follows prior appropriation: first in time, first in right. Catlin's 1888 decree is senior to Corrigan's 2015 well. Beneficial use is necessary to perfect and maintain a water right, but it does not make a junior right equal to a senior right, and it does not authorize injury to a senior appropriator.
The no-injury rule. A junior appropriator may divert only if the diversion does not injure senior rights. The Division measured 210 acre-feet per year of depletion, which is the injury. Corrigan's 'reasonable use' argument is not a defense; reasonableness determines whether a use is beneficial, not whether it can override priority.
The dry-year point does not help him. Nonuse in dry years is not abandonment unless the senior intended to abandon, and abandonment requires a judicial determination. The 'futile call' doctrine can excuse a senior call where the senior could not physically divert even with the junior's water, but that is an evidentiary issue. Here the Division measured actual depletion, so Corrigan would have to prove that Catlin could not have diverted in those years despite the water. The record does not support that.
Conclusion. Beneficial use does not protect him from curtailment.
2. May Corrigan continue pumping while he applies for a plan for augmentation, and what must he show to obtain one?
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He may not continue pumping lawfully. Tributary groundwater is subject to the same priority system as surface water. A well that depletes a natural stream must be operated under a decreed plan for augmentation or an approved substitute water supply plan unless an exemption applies. Corrigan's 90-acre irrigation well is not an exempt small domestic or livestock well, and there is no designated-basin exemption on these facts. The cease-and-desist order is authorized.
What a plan for augmentation requires. An application to the water court in the division where the well is located (Division 2 for the Arkansas), notice to affected parties, and proof that replacement water will be provided so that senior rights are not injured. The plan must be decreed; an application alone does not suspend administration.
Temporary relief. A substitute water supply plan may allow temporary operation if the State Engineer approves it and replacement water is actually supplied. That is discretionary and requires a showing of no injury, not a promise to find water later.
Practical advice. Shut down the well, line up replacement water - leased storage, purchased agricultural water, or a recharge project - and file the augmentation plan promptly. Pumping in the meantime risks enforcement and undermines the good faith needed for temporary approval.
3. Evaluate Corrigan's takings argument and the significance of the ditch's non-diversion in dry years.
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The takings argument fails. Colorado water rights are usufructuary: a right to use water, held subject to the prior appropriation system. A well permit does not include a right to injure senior appropriators. Curtailing a junior use to protect senior rights is an exercise of the state's police power and its constitutional role in administering water, not a physical or regulatory taking. The investment-backed-expectations factor cuts against Corrigan because he drilled with notice of the priority system, and the economic impact, while real, does not strip the right of all value - he may still use the water under a decreed augmentation plan.
Non-diversion in dry years. The ditch's failure to divert does not eliminate its right. Abandonment requires intent plus a judicial decree, and the futility-call doctrine applies only where the senior could not have diverted even with the junior's water. The Division's measurement of 210 acre-feet per year undercuts futility here. If Corrigan wants to press the point, he must produce hydrologic evidence that Catlin's diversions were physically impossible in the relevant years - not merely that Catlin chose not to divert.
Bottom line. The order should be upheld; Corrigan's remedy is an augmentation plan, not a constitutional challenge.