Nevada Supreme Court Weighs in on Conjunctive Management

Conjunctive management recognizes there may be a hydrological connection between groundwater and surface water within an area. This means, drawing down groundwater may affect the availability of surface water, and vice versa. In prior appropriation states like Nevada, where senior water rights have priority, surface water rights will generally trump groundwater right. In January 2024, the Nevada Supreme Court weighed in on Nevada’s conjunctive management law.

Points of Contention

With limited water availability in the arid west, it is increasingly necessary to manage both groundwater and surface water as a single management unit to protect senior water rights. However, there is an understandable reluctance on the part of some junior water rights holders to curtail water use that has gone unchecked for decades.

One point of contention is whether the best available science supports the curtailment of a junior water right– does the best available science support finding a specific groundwater use is depleting the source of a senior surface water right? How much can a junior water rights holder still use and not affect the senior water rights? The Nevada State Engineer will determine what constitutes “best available science.”  Is it a full-blown scientific model, or will something less suffice?

A second point of contention has been whether the State Engineer has the authority to manage the waters of the State conjunctively. We finally have the answer: In January 2024, the Nevada Supreme Court issued its decision in Sullivan v. Lincoln County Water District recognizing the power of the State Engineer to conjunctively manage surface waters and groundwater. Case Nos. 84739, 84741, 84742, 84809, 85137, 2024 Nev. LEXIS 4 (Jan. 25, 2024).

The Court’s Decision

In reaching their decision, the Court primarily relied on provisions of the Nevada Revised Statutes (NRS) (state.nv.us) prohibiting the impairment of vested/existing water rights, “regardless of the water source.” The Court noted that “[a]ll statutorily granted water rights in Nevada are given subject to existing rights” and “[b]ecause vested water rights by definition exist prior to the grant of statutorily granted water rights… no statutorily granted water right may impair vested water rights.” Id. (citations omitted). In sum, the Court found that no matter the source, ground or surface water, the State Engineer must not allow any impairment of vested water rights. Hence, the State Engineer must have the power to conjunctively manage both sources of water in Nevada.

The Court’s decision also recognizes the legislative policy declared at NRS 533.024 “which require the State Engineer to ‘consider the best available science in rendering decisions concerning the available surface and underground sources of water’ and ‘[t]o manage conjunctively the appropriation, use and administration of all waters.” As such, the Court notes these policy declarations support the finding that the State Engineer has power to conjunctively manage the waters of the State of Nevada, decisively settling years of litigation over the matter.

What’s Next?

For years the State Engineer attempted to conjunctively manage but was hamstrung by scientific uncertainty regarding the hydrological connection between groundwater and surface water sources, leading to exhaustive litigation concerning the State Engineer’s management orders. The new Model on the Humbold River, reportedly nearing completion, will be integrated into the State Engineer’s future orders that will likely be further tested in the courts. Likewise, submission of Scientific Reports in the Lower White River Flow system were presented to the Nevada Court that will now determine if these reports are sufficient substantial evidence to support the State Engineer’s regulation orders.  It will be interesting to follow the litigation to see what level of “best available science” will withstand the scrutiny of the courts.

You might be interested in this article about Nevada Water Law.