James J. Jacobs, UW Professor, Natural Resource Specialist
Gordon Fassett, State Engineer, Cheyenne
Donald J. Brosz, Associate Director, Wyoming Water Research Center
Cooperative Extension Service
College of Agriculture
Wyoming Water Research Center
University of Wyoming
Wyoming water law dates back to territorial days and is based on the "doctrine of prior appropriation." Under this doctrine the first to put the water to beneficial use has the first right, or "first in time is first in right." Therefore, water rights in Wyoming, and in most of the western states, are regulated by priority. This means the earliest rights are entitled to water during periods of limited supply, while those with later rights are denied water during these times.
The Wyoming Constitution provides that water of all natural streams, springs, lakes, or other collections of still water be the property of the state.
The state engineer is the chief administrator of Wyoming waters. In administering these waters, the state is divided into four water divisions. Water division 1 includes the North Platte and South Platte River drainages and the Little Snake and the Niobrara River drainages. Water division 2 includes all drainages north of the Niobrara and North Platte River drainages and east of the Big Horn Mountains. Water division 3 includes the Big Horn and Clark's Fork River drainages, and water division 4 includes the Green, Bear, and Snake River drainages. A Wyoming map showing the water divisions is found below.
A water division superintendent administers the waters of each water division with assistance from water commissioners and hydrographer-commissioners. These four superintendents and the state engineer constitute the state board of control. The board meets quarterly to adjudicate or finalize water rights and to consider other matters pertaining to water rights, such as change in point of diversion and other amendments or corrections of water rights.
When you write the state engineer for necessary forms and information, address correspondence to:
State Engineer's Office
4th Floor East
Cheyenne, Wyoming 82002
You can also obtain information from each of the water division superintendents' offices, which are located in these Wyoming cities:
Water division 1:      Torrington
Water division 2:      Sheridan
Water division 3:      Riverton
Water division 4:      Cokeville
Prior to statehood in 1890, a water right could be established by a procedure predicated on the use of water and the filing of a claim with territorial officials. Water rights with priority dates before 1890 are termed "territorial" water rights. Since statehood, the only way a water right can be acquired in Wyoming is by securing a permit from the state engineer. Water rights cannot be obtained by historic use or adverse possession in any case. Wyoming water law requires that you follow certain procedures to obtain a valid water right. Following is a summary of these procedures for surface and ground water.
Wyoming's first surface water laws were enacted in 1875. More comprehensive laws were adopted along with the state constitution in 1890. In brief, and paraphrased, these laws state:
If there is not sufficient water to furnish 2 cfs to each pre-March 1, 1945, water right, but more than enough to furnish 1 cfs to each of such rights, then the surplus water is divided among those rights on a pro rata basis. If there is so little water that each pre-March 1, 1945, right cannot receive 1 cfs, they are regulated on a strict priority basis.
Any water beyond that required to furnish 2 cfs for each 70 acres of pre-March 1, 1945, water rights is first allocated to rights with priority dates after March 1, 1945, and before March 1, 1985. Wyoming's Excess Water Law states that each water right with a priority date of post-March 1, 1945, but pre-March 1, 1985, is entitled to 2 cfs per 70 acres before any water is made available to post-March 1, 1985, water rights. If there is not sufficient water to furnish 2 cfs to each post-March 1, 1945, and pre-March 1, 1985, water right, but more than enough to furnish 1 cfs to each of these rights, the excess water is divided among those rights on a pro rata basis. If there is so little water that each post-March 1, 1945, and pre-March 1, 1985, water right cannot receive 1 cfs, the rights are regulated on a strict priority basis.
For post-March 1, 1985, water rights, those rights are entitled to 1 cfs per 70 acres only after all pre-March 1, 1985, rights have received 2 cfs per 70 acres. Under Excess Water Law, the post-March 1, 1985, water rights may also receive 2 cfs if water is available.
The state engineer may issue you a permit for water storage and development of a spring. File a simplified form, which does not require maps and plans prepared by a registered engineer or surveyor, for the following water uses:
A reservoir is entitled to be filled in priority once each year if water is available. If water remains unused in the reservoir at the end of the normal use period, the water is designated as carry-over storage and counts toward providing water to meet the following year's supply for appropriation.
The 1986 Legislature declared that instream flow for maintenance or improvement of existing stream fisheries is a beneficial use of water than can be provided from natural streamflows or from storage water. A statutory procedure was established for the state, represented by the Wyoming Water Development Commission, to appropriate specified flow rates for instream flows in segments of streams identified by studies and reports of the Wyoming Game and Fish Commission. The WWDC must conduct a hydrologic study to determine whether the instream flow can be provided from the natural flow of the stream or whether storage water from an existing or new reservoir will be needed for part or all of the instream use. The WWDC report is supplied to the state engineer for his consideration. If storage water is needed from a new reservoir project, normal legislative project authorization procedures must be followed by WWDC.
After receiving reports from the Game and Fish Commission and WWDC, the state engineer may conduct his own evaluation of the proposed appropriations for instream use. Before granting or denying a permit for instream flow in the specified stream segment, the state engineer must conduct a public hearing and consider all available reports and information. If granted, an instream flow permit can contain a condition for review of continuation of the permit at a future time.
The instream flow appropriation goes into effect the date the state engineer approves the permit. The water right cannot be adjudicated by the board of control for three years thereafter. An instream water right has a date of priority as of the date that the application was received and recorded by the state engineer, and all senior priority water rights must be recognized in administration of the stream.
The state engineer cannot issue an instream flow permit if it would result in loss of a portion of Wyoming's consumptive share of water allocated by interstate compact or U.S. Supreme Court decree, or if it would result in more water leaving Wyoming than allocated for uses downstream of Wyoming.
Other persons can appropriate water for instream flow on a segment of a stream within 1 mile of the Wyoming state line or within 1 mile upstream from major reservoirs on the Big Horn, Green, and Snake rivers.
The first Wyoming ground-water laws were enacted in 1945 and amended in 1947. A new ground-water law went into effect March 1, 1958, repealing and replacing the 1945 and 1947 laws. Major amendments were made in 1969.
The law defines domestic use as household use, including the watering of lawns and gardens for noncommercial family use, where the area to be irrigated does not exceed 1 acre. The quantity of water to be pumped for family or stock use shall not exceed 25 gpm. A well may supply water to more than one, but not more than three, single-family dwellings and still be considered a domestic use provided that:
Stock watering use is defined as the normal watering of livestock, including any project whereby water will be piped to no more than four points of use within 1 mile of the well. Large feedlot operations or any project whereby the water will be piped to five or more points of use, or the points of use are greater than 1 mile from the well, are considered miscellaneous use.
The same general procedures to acquire surface-water rights apply to acquiring a ground-water right:
The board of control may designate a control area where:
You may change a well location within the same aquifer in the vicinity of the original location or the well depth without loss of priority, provided you have obtained approval from the state board of control if the ground-water right has been adjudicated or the groundwater right has not been adjudicated but the water has been applied to beneficial use. In cases involving domestic and stock water wells that are not adjudicated but whose water has been applied to beneficial use, the state engineer may approve a change of location. If the right is not adjudicated and the water has not been applied to beneficial use, approval for the change in location may be granted by the state engineer. For all wells, the state engineer may approve a change in well location even if the water has not been put to a beneficial use.
Wyoming water law defines the preferred uses of both surface and ground water and lists them in the following order:
All uses of water other than those listed as preferred uses are considered non-preferred.
When the water supply is insufficient to meet water rights, rights with a preferred use do not take precedence over a non-preferred use. The priority date of a water right, preferred or non-preferred, determines who is entitled to water. The only way you can obtain a preferred right for a non-preferred prior right is by purchase or by condemnation through court action. The right of condemnation cannot be used by industrial concerns to obtain water rights. However, ground-water wells yielding 25 gpm or less and used solely for domestic and stock purposes do have preferred rights over wells for all other uses regardless of date of priority.
Example: An irrigation water right (non-preferred use) with an early priority is entitled to use water even when it may involve denying water to a municipality (preferred use) with a later right. The municipality may acquire, through condemnation if necessary, the earlier irrigation right and change it to municipal use, provided just compensation is paid.
To keep a water right valid when changes are made in the point of diversion, in the location of a well, in the location of an irrigation ditch, or similar circumstances, you must secure permission. Do this by petitioning the state board of control if the water is adjudicated. If it is not adjudicated, send your petition to the state engineer.
In most instances, obtaining permission for changes does not change the priority date of the water right but keeps the water right up to date and legal. Public hearings on the changes may be held to ensure that no injury occurs to the other water right holders because of the change. Keep the water right in proper standing so no legal questions are raised concerning its validity.
If you own a water right and wish to change it from its current use to another use, or from the place of use under the existing right to a new place of use, you must file a petition requesting permission for a change. The petition sets forth all pertinent facts about the existing use and the proposed change in use. When you request a change in place of use, all pertinent information about the existing use and the proposed place of use shall be specified in the petition. The board may require that an advertised public hearing be held at your expense. The petitioner shall provide a transcript of the public hearing to the board. The change in use, or change in place of use, may be allowed.
If such an allowance is granted, the quantity of water transferred by the granting of the petition shall not exceed the amount of water historically diverted under the existing use. Furthermore, the historic rate of diversion and the amount consumed cannot exceed that under the existing use. Finally, such a petition, if allowed, shall not decrease the historic amount of return flow, or in any manner injure other existing lawful appropriators. The board of control considers all facts it believes pertinent to the transfer. These may include the following:
In all cases where the matter of compensation is in dispute, the question of compensation shall be submitted to the proper district court for determination.
Wyoming law now provides that any time you subdivide a parcel of land with water rights attached, you (the developer) must dispose of the water rights in one of three ways:
Each of these actions requires review by the state engineer's office or the state board of control before the subdivision can be approved by the respective county.
A water right for surface or ground water not used for five successive years when water is available to satisfy the right is considered abandoned, but a statutory procedure must be followed to bring about legal abandonment. The law provides a procedure for abandonment, but it must be brought by an affected water user who has a priority equal or junior to the right being abandoned, or by the state engineer. If a right is declared abandoned, the user forfeits all water rights, easements, ditch rights, and the like, and the water again becomes subject to appropriation. Water must have been available but not used for an abandonment to take place. Wyoming law provides standing so that abandonment action can be brought by a pre-March 1, 1945, water right holder, even though senior in priority, against another pre-March 1, 1945, water right holder to protect the right to surplus water.
In Wyoming a valid right to the use of water may be acquired only by following the procedures established by state law for both surface and ground water.
Water users should be sure of the status of their water rights. Check the records in the county clerk's office, or through the state engineer's office. The records indicate the appropriation amount, priority of the right, and how and where the water is to be used. If there are any questions, check with the state engineer's office and request complete information on the status of the water right in question.
Persons seeking admission, employment, or access to programs of the University of Wyoming shall be considered without regard to race, color, national origin, sex, age, religion, political belief, disability, veteran status and marital or familial status. Persons with disabilities who require alternative means for communication or program information (braille, large print, audiotape, etc.) should contact their UW Extension Office. To file a complaint, write the UW Employment Practices/Affirmative Action Office, University of Wyoming, P.O. Box 3354, Laramie Wyoming 82071-3354.
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