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A History Based on Need

Water Law in Colorado is directly tied to the state’s semiarid climate and man’s first endeavors to eke a living from the land. Anasazi Indians constructed storage ponds and irrigation channels as early as 1100 AD. From these first examples in the Four Corners region, Colorado’s water projects have grown into gigantic storage reservoirs and trans-mountain diversion systems.

Flowing River

When large numbers of settlers began to occupy the state in the mid-1800s, they soon became aware of the critical problems surrounding water. At this time, the greatest quantity of water was used and dictated by mining operations. Disputes soon arose and accelerated giving way to “Water Wars” in 1874. Miner’s Courts were established to resolve conflicts. These courts handled water claims in a manner similar to land claims or, the first on the land had the first claim. And so it became with the first water law decisions in Colorado leading to the phrase, “first in time, first in right”. Unlike riparian or littoral water rights established in eastern states based on ownership of the land along watercourses, Colorado’s water laws evolved from the realities of mining and its needs. Using this doctrine, Colorado became the first state to formally adopt the concept of prior appropriation for inclusion into the Colorado Constitution in 1876.

Appropriation and Beneficial Use

Prior appropriation is reliant upon the legal ownership of water rights. As stated in 1996 by the Agricultural Water Conservation Task Force, a water right “is based on diverting a given quantity of water at a specified site under a specified priority and applying diverted water at an identified location for a defined purpose”. This defined purpose must also be considered a beneficial use. Appropriated water is allocated as a senior priority or junior priority, “the first in time, first in right” doctrine again. An explanation of senior and junior water rights can be understood from the following scenario.

A court approved water right, also called an adjudicated water right, totals 5 cubic feet per second (c.f.s.). It is shared by 3 users; one holding senior rights to 2 c.f.s., one with junior rights for 2 c.f.s. and the third with junior rights of 1 c.f.s. When the stream or ditch is running at 5 c.f.s then all users would receive their allocated water right. However, if drought or other reasons reduce the flow to 3 c.f.s. the senior priority right of 2 c.f.s. would be honored, the first junior priority would receive half or 1 c.f.s. and the last junior priority would receive nothing. The system of senior and junior priorities explains why some water rights are more valuable or constant than others. Another aspect of prior appropriation contains the “use it or lose it” clause. If water is not applied to a beneficial use over a 10-year period it is considered abandoned and can be appropriated by another individual or entity.

As stated in the Colorado Revised Statutes; beneficial use is defined as, “the use of that amount of water that is reasonable and appropriate under reasonably efficient practices to accomplish without waste the purpose for which the appropriation is lawfully made . . .” Beneficial uses include municipal, domestic, industrial, recreational, agricultural, and environmental needs. The state’s original demand for mining purposes no longer holds the greatest need. Multipurpose use of the state’s water resources now exceeds anything foreseen 100 years ago.

Climate Limitations

Annual precipitation averages are compiled by the USDA-NRCS National Water and Climate Center. Over the past 10 years, our area of Colorado received between 12″ – 15″ of precipitation. Compare this to the 32″ – 36″ averaged in the same reporting period for eastern Iowa or the 35″ – 40″ received in western New York State.

Most of the state’s precipitation comes in the form of mountain snows. When these snows melt in the spring, the runoff provides annual renewal of water for reservoir storage. It also provides recharge for ground waters. It is important to remember that while mountain snow packs are measured in feet, they actually only yield inches of water when the snow melts. Since the state lacks predictable and generous rainfalls or proximity to large natural lakes and rivers; Colorado’s water and it’s water laws will always be challenged to keep an adequate supply flowing to agriculture, cities, and manufacturing interests.

Administration of Water Rights

The State Engineer administers all waters within the state under constitutional provisions. The state is subdivided into seven water divisions, each with a Division Engineer and staff. Water Commissioners administer districts within these divisions. The Water Commissioner is responsible for local water issues, information and public relations at the district level. The Colorado Division for Water Resources houses the State Engineer’s office in Denver. The office has numerous publications available for purchase including listings for divisions and district offices and fee structure information on various water related licensed services or requirements. Information on contacting the State Engineers office can be found in the reference section at the end of this chapter.

Water Sources

Most cities, even in Colorado, rely on a combination of surface and ground water wells to meet their needs. Using systems of reservoirs, pipelines and wells ensures that urban entities can provide an adequate and constant flow of clean water to their users. These systems were constructed very early in our state’s history as a response to population increases and a growing agricultural economy. An example of this process can be found by reading the early history of Greeley, Colorado. Today, vast quantities of water are diverted from western slope rivers and reservoirs for use on the Front Range. But, complex and highly organized urban water departments do not service landowners on rural land parcels.


In rural settings within subdivisions most Colorado landowners rely solely on domestic wells for their water. In Adams, Arapahoe and Weld counties, parcels from 3 to 35 acres are usually developed with a single well per home site. These residential well permits allow only limited outside watering for lawns or landscape maintenance.

When people purchase land that does not have a developed well then they must go through the state’s Water Engineer’s office. The office offers consumers a list of approved drilling and pump installation contractors who, as part of their drilling service, will actually acquire the proper permits for well construction. The depth and amount of water produced by these wells is controlled by the geology or rock formations underlying the area. These aspects have been studied and mapped by the Water Engineer’s staff and determine how many wells can be permitted in any given area.

Rarely do owners of subdivision size land parcels have irrigation wells for outside watering needs. The term “irrigation well” refers to wells used for agricultural purposes and is, again, under the jurisdiction of the Water Engineer’s office.

Frustrated by the relatively small amounts of water produced by residential wells and the limitation of outside watering permitted, some landowners seek to develop ponds to increase their ability to accomplish outside watering. In the Midwestern and eastern states where rainfalls and ground water are both higher, it is a common practice to build a “pit” reaching into the ground water table. For aesthetic reasons these pits are often shaped, grassed, and given landscape treatments to look like natural ponds. The development of such a feature in Colorado is seldom possible. The water table or the distance from the surface of the ground to any appreciable water beneath is usually too great a reach for excavation. And, the state of Colorado considers water that can be developed by excavation to be an open well, therefore requiring a permit. A good “rule of thumb” to remember is that if you have to dig for it, a permit from the Water Engineer’s office will be required.

Surface Water

In Colorado, surface water is any water in any form that flows on the land surface. This includes rivers and streams, intermittent creeks or springs, irrigation canals and ditches, rainfall and snow. Historically, these are the waters first claimed and developed in the state and fall under the principal of first in time, first in right. Some original property owners with water rights divide their appropriation when subdividing their land and include their water rights for the new landowners under provisions in the state statutes. They will each have less water than the original total and have junior priority rights. In times of drought, it is likely that there will not be enough surface irrigation water.

Impounding of water by building small dams or other structures may affect the storage priority rights and capacity of downstream users. Structures built to hold seasonal waters can constitute a hazard to others if they fail during intense storms when flash floods occur.

Consequently, only small structures or diversions can be built to capture rain or snow water. Information, surveys and designs for this type of small, seasonal use structure is provided by the Natural Resources Conservation Service field office staff at no charge.

Additional Resources

Colorado Division of Water Resources

Office of the State Engineer

1313 Sherman Street, Room 818 Denver, CO 80203

Telephone: (303) 866-3581

FAX: (303) 866-3589

Web Page:

United States Department of Agriculture

Natural Resources Conservation Service

Local Field Office Information:

Byers, Colorado

133 West Bijou Avenue

(303) 822-5257

Brighton, Colorado

57 West Bromley Lane

(303) 659-7004