The historic drought of 2026 has spurred many questions about water rights, water right administration, and water right calls.  In an effort to debunk some of the intricacies of Colorado water rights, we provide the following facts and resources.

Prior Appropriation System

Water rights in Colorado are goverened by the Prior Appropriation System, meaning "first in time, first in right." In other words, the first person to take water from a stream or underground aquifer, put it to beneficial use, and file for that water right in water court, has the first right to its use.  This is the "senior" water right holder.  All subsequent claims to that stream or aquifer will be "junior" water rights, some are more junior than others.  In times of limited water resources (like drought), senior water right holders can place a "call" for water, meaning "junior" water right holders will have to turn their water off (in the order of priority) to satisfy the senior holder's claim.  

Water Uses

The state has four primary water uses: Agriculture, Municipal, Self-supplied Industry, and Recreation/Environment.  The first three are consumptive uses, meaning that at least a portion of the water used will be permanently removed and no longer available for reuse. Conversely, uses which leave flows in rivers (recreation and the environment) are referred to as non-consumptive uses. 

Because the first people in the state to divert and use water were farmers and ranchers, the majority of water that stays in the state goes to agriculture (86.7% of statewide water delivery, 89% of statewide consumptive use).  Municpal water (water that goes to  homes, yards, businesses, firefighting and small-scale industry) accounts for 6.7% of statewide water delivery and 7% of statewide consumptive use.  Self-supplied Industrial water use (water for energy development, snowmaking, thermoelectric power generation, food processing and large industries, such as breweries) accounts for 1.1% of the statewide water deliveries and 4% of statewide consumptive use.  Non-consumptive uses (outdoor recreation and the environment) currently account for about 5.5% of total statewide water deliveries but 0% of statewide consumptive use.

Interstate Water Deliveries

It is important to note that the figures stated above only represent the water used by Colorado residents/businesses.  However, not all water that falls in the state (in the form of rain, snow, hail, sleet) stays in the state.  Due to delivery obligations from interstate compacts and agreements, less than 40%  of the water that falls in the state is consumed within the state.  60% of the water that originates in Colorado leaves Colorado for downstream users in other states.  

The Colorado River CWeompact (involving seven western states and Mexico) is one of these interstate compacts that has received a lot of publicity in recent years.  Worsening drought conditions and population growth have put a strain on the limited water resources, resulting in legal battles between states.  

Division of Water Resources

The Colorado Division of Water Resources (DWR) administers water rights in the state of Colorado to ensure that waters are diverted in accordance with the Prior Appropriation Doctorine and Colorado state laws.  DWR's purview not only applies to diversions through ditches and canals, it also applies to dams and groundwater (wells).

The Division of Water Resources divides the state into 7 main divisions that are then broken into districts.  Middle Park (Grand and Summit Counties are in  Division 5.  Our districts are 36, 50, 51, and a little bit of 52 and 53.  

Understanding Water Right Priorities

 Knowing that water rights in Colorado have different "priorities" is one thing, but understanding where your water right falls in the priority line is completely different.  When water is flush and rivers are in a "free water" state, it may not matter.  However, when drought conditions persist, there is not enough water to go around.  In these situations, it is critical that understand where your water right stands.  Fortunately, the Colorado DWR has tried to make it is easy for water right holders to identify their priority ranking - that is through the use of ADMINISTRATION NUMBERS.

Administration Numbers

Water decrees will list an Administration Number, Appropriation Date (date that water is first diverted and put to beneficial use),  and Adjudication Date (date the water right was formally settled in water court).  Some water right decrees may also list a "Previous Adjudication Date" - if listed, this is the date used for determining priorities and used in the Adminstration Number calculation. Administration Numbers are a calculated number developed by the Division of Water Resources to provide a simple and efficient method of ranking decrees in order of seniority. 

When comparing Administration Numbers between water rights, the LOWER the admin number, the more SENIOR the water right.  The GREATER the admin number, the more JUNIOR the water right. 

• For reference, the most senior water right in the state of Colorado has Admin Number of 831.00000.  It belongs to the San Luis People's Ditch and was appropriated on April 10, 1852 (831 days after 12/31/1849).

Check out your water right's details at https://dwr.state.co.us/Tools/WaterRights/NetAmounts

Administration Numbers are computed as follows:

•  If the Appropriation Date is later than the Previous Adjudication Date, then the left side is the number of days between 12/31/1849 and the Appropriation Date, and the right side is zero (.00000)
• If the appropriation date is the same as, or earlier than, the Previous Adjudication Date, then the left side is the number of days between 12/31/1849 and the previous adjudication date, and the right side is the number of days between 12/31/1849 and the Appropriation Date.
• Here is a link to a date calculator where you can calculate the number of days from 12/31/1849 to your Appropriation Date or Previous Adjudication Date: https://www.timeanddate.com/date/duration.html

Example Water Right Comparison

Interesting Facts about Water Rights in CO

• Water right decrees (found on the Colorado Division of Water Resources pages above) do not tell you who owns the water rights.  Ownership  information comes from recorded deeds (the County Clerk/Recorder) and ditch company share books.  Water rights are considered person property rights that can be sold, bought, transferred or inherited.
• Water rights can be separated from the land in Colorado and sold to someone or some entity far far away. Thus, you do not automatically own the water on or running through your property.  You also do not have the automatic right to use or divert it. 
• A water right holder that owns a water right on your property has an implied easement to access that water right on your property.  You cannot stop them from accessing it or maintaining it.  Likewise, you cannot change or modify that water right (ditch, pond, etc) without permission of the water right holder(s).  

Wells

Wells are a whole different ballgame than ditch rights described above.  Homeowners must apply for a well permit from DWR.  Once approved, the permit will outline what uses are or are not allowed.  A common type of  well permit is  the "Household Use Only" permit, issued for ordinary household uses in a single-family dwelling that does not allow for outside water or livestock watering.

Dams and Ponds

Dams are categorized into one of the following five categories, each having specific construction and administration requirements: Jurisdictional Size Dams, Non-Jurisdictional Size Dams, Livestock Water Tanks (LWT), Erosion Control Dams (ECD), Exempt Structures. Requirements for constructing a new dam, or altering or repairing an existing dam, generally include some form of application and approval process. 

Constructing a dam to create a reservoir does not assure the owner the right to store water; nor does having or obtaining a water right constitute approval to construct a dam. Water rights are obtained (decreed) through Colorado Water Court and then administered by the state engineer. 

For more information on dams check out this link, or for a Beginner's Guide on Ponds, check out this link.