License to Pump

Groundwater Permitting in the West

Although it shares state administration of groundwater permitting in common with other southwestern states, Colorado’s system is uniquely court-driven and particularly complex. Relative to other southwestern states, Colorado exercises close control over its groundwater. Property rights and the entity exercising jurisdiction over permitting vary depending upon the relevant aquifer. These different rules provide varying degrees of protection, from close guarding against depletion of streams in the case of tributary groundwater, to planned depletion of non-tributary groundwater.   Continues Below »

Data & Analysis

Special Permitting Areas in Colorado

Even if a map does not show a special permitting area, one might still need to gain permission to pump groundwater. Highlighting special permitting areas helps us understand an important aspect of how a state has chosen to regulate groundwater differently in certain areas, compared to its ‘default’ regulatory arrangements.

Special Groundwater Permitting Area(s) i
Designated Groundwater Basins
State Groundwater Management Agencies
Colorado Department of Natural Resources,
Division of Water Resources
Colorado Ground Water Commission
Property Rights?
Prior Appropriation?
Rule of Capture?
Correlative Rights?
Reasonable Use?

Generally applicable statewide? Yes.

Map of water rights by state



The Colorado constitution dedicates the unappropriated waters of any "natural stream" and the "waters of the state" to the public, and guarantees the right to appropriate those waters according to the prior appropriation doctrine.1 The groundwater revolution, however, tested and transformed these terms. Throughout the 1950s and the 1960s, both the courts and the legislature wrestled with how to reconcile the assumptions and protections of established Colorado water law with the different historical and hydrological qualities of Colorado groundwater—especially along the suburban communities along the Front Range and the farming communities above the High Plains-Ogallala Aquifer.2 On the other side of that revolution, Colorado has emerged with a complicated body of groundwater law, where property rights and jurisdiction vary depending upon the relevant aquifer.

Groundwater accounts for about 14% of the state's total freshwater use.3 Approximately 84.4% of groundwater withdrawn is used for agriculture.4 Colorado groundwater is also used important for domestic consumption, accounting for about 100% of individual household water use and 15.3% of municipal supplies.5


Summary of the Law

Types of Groundwater and their Regulation

Colorado groundwater law is a "rule with three exceptions." The rule, a product of both case law and the Water Rights Determination Act of 1969, is that groundwater supplies that are tributary to "natural streams" qualify as "tributary groundwater," and are therefore governed by the same doctrines and procedures as the surface waters of Colorado—those of prior appropriation and the Colorado water court system.6 As a result, holders of rights to tributary groundwater must obtain a decree in water court to establish their right, and they must also obtain a well permit from the State Engineer's Office ("SEO").7 The water court decree establishes the basic attributes of the right to tributary groundwater—most importantly, its priority and authorized annual quantity, but also its point of diversion, place of use, and type of use.8 Priority remains fixed, and the consumptive use aspect of the authorized annual quantity cannot increase, but that attribute and the other attributes can be changed by modifying the decree through the water court process.9 The well permit signifies administrative approval by the SEO, which sets rules and regulations for tributary groundwater, and enforces priority calls in times of shortage.10  Tributary groundwater is most prominent in the large alluvial basins of the Rio Grande and the South Platte and Arkansas River Basins.11  The basic standard that drives the permitting process is that pumping will not be allowed if it adversely affects surface water rights.12  In the Denver basin[SMR1 , about half of all pumping is of tributary groundwater.13

The largest exception to the rule of tributary groundwater is that of designated groundwater. Under the 1965 Colorado Ground Water Management Act, groundwater basins that do not underlie a flowing stream, or do not support long-established surface water rights, are classified as designated basins.14 (Eight basins have been so designated, located above the High-Plains Ogallala Aquifer in eastern Colorado.)15 Designated groundwater does not qualify as "waters of the state" according to the Colorado constitution.16 It is governed by a softened version of the prior appropriation doctrine: senior wells are entitled to priority protection against unreasonable pumping by junior rights, but not to the maintenance of historical groundwater levels.17 Pumpers in designated basins must obtain well permits from the Colorado Ground Water Commission ("Commission"), not the SEO; but the review process is similar to that for tributary groundwater, and the Commission sets rules and regulations to determine whether new wells would impair existing ones.18

The second exception is that of non-tributary groundwater. This is groundwater located in confined, deep aquifers, which has little or no connection to surface flows or to tributary groundwater, and is located outside a designated basin.19 The statutory regime for non-tributary groundwater makes clear that this is a non-renewable resource,20 mandates a minimum 100-year aquifer life, and does not apply the doctrine of prior appropriation, but rather a policy of planned depletion, and allocates supplies according to overlying land ownership.21 Well permits for non-tributary groundwater are obtained from the SEO, which allocates the total available groundwater based on the 100-year aquifer life; this enables the sum of all non-tributary groundwater well permit holders to deplete the aquifer 1% each year.22

Due to their high value as residential and municipal supply sources, the Denver Basin Aquifers of the Front Range have modified rules for both non-tributary and designated groundwater. Non-tributary groundwater located in the Denver Basin Aquifers of the Front Range is subject to a slightly higher restriction: no more than 98% of the groundwater pumped from these aquifers can be consumed, and the remaining 2% must be returned to surface stream system, to ensure that surface water and tributary groundwater rights are not affected.23 As for designated groundwater in the Denver Basin Aquifers, well pumping is subject to the same 100-year aquifer life as for non-tributary groundwater (rather than the modified prior appropriation doctrine for designated groundwater), and is permitted according to overlying land ownership by the Commission.24

The final exception is that of not non-tributary groundwater. This is groundwater located in the Denver Basin Aquifers that is slightly more connected to surface systems than non-tributary groundwater.25 Because of that higher connection, well permits to not non-tributary groundwater (which are also obtained from the SEO) require an augmentation plan (see below) to compensate for the depletions to streamflow caused by the pumping.26 As with non-tributary groundwater, the allocation of not non-tributary supplies is based on a 100-year depletion schedule.27 

Enabling out-of-priority groundwater development: Augmentation Plans

Holders of junior tributary groundwater rights may obtain permission from the SEO to pump during times of shortage (when they would otherwise subject to priority administration) if they obtain approval of an "augmentation plan" or "substitute water supply plan" from the SEO.28 Typically, such a plan requires out-of-priority pumpers to compensate for the depletions their pumping causes by securing additional water supplies from other sources—commonly by leasing other water rights in times of shortage.29 Permittees to not non-tributary groundwater must obtain approval of an augmentation plan as a condition of their permit.30

Special Groundwater Districts

Aside from the SEO and the Commission, two other entities play a role in the regulation of groundwater in Colorado. Water Conservation Districts ("WCDs") cover interstate streams, such as the Rio Grande and the Colorado and Republican Rivers, but they exert important powers over groundwater management policy in those river basins as well.31 In designated basins, Groundwater Management Districts ("GMDs") work with the Commission and the SEO, but they have the ultimate say in the regulation, use, control, and administration of well permits.32

Next: Law & Practice »

Special Permitting Areas: How Colorado Compares

Law and Practice

Colorado has a very thorough groundwater law regime, but still faces challenges in implementation.  Effective groundwater management requires information; for example, information about groundwater is required to form augmentation plans, determine which type of groundwater is contained in a certain aquifer, and analyze how dewatering mines will affect wells, among other things.33  One key challenge in groundwater management in Colorado is the lack of data about groundwater, and specifically the lack of reliable information on aquifer characteristics.34  The lack of reliable information on aquifer characteristics leads to differences among groundwater models, which then produce confusion and disagreements in water courts.35 There are also budgeting and scheduling constraints to conducting groundwater modeling that will produce this type of information.36 

Another challenge to groundwater management in Colorado is a communication problem.    Groundwater experts must learn to better communicate their very technical findings with non-scientist audiences, including judges, attorneys, regulatory agencies, and other stakeholders.37



Compare Special Permitting Areas by State

In this Report

Read Insights: The West

There is a spectrum of legal interventions used to manage groundwater withdrawals in each of the southwestern states. Permitting powers can be managed at different levels of government, requiring a review of a wide-range of criteria or requiring metering, monitoring, and reporting standards — what are the regional trends

Compare and Contrast States

The significant diversity of groundwater withdrawal permitting in the southwest provides a laboratory of regulatory arrangements, the examination of which provides opportunity to identify tools for sustainable groundwater management in your community or state — how does your state compare to its neighbors?

Read and Learn: Your State

All southwestern states have introduced the concept of groundwater withdrawal permitting into their state laws. Some states were early adopters of groundwater withdrawal permitting, while other states have only incorporated a widely applicable power recently — which state do you live in?