Beneficial Use

As defined by the 1969 Water Right Determination and Administration Act (C.R.S. 37-92-101 et seq.):

Beneficial use is 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.

Therefore, beneficial use stands as the “basis, measure and limit of a water right,” (WEC, 2015:7). The amount needed for each beneficial use is determined by the amount required to move the water to the location of use, plus the amount needed for consumptive use (see the “Water Uses” section for a more detailed discussion of consumptive use). The portion of the water not consumptively used after put to beneficial use (returning to surface waters or aquifers) is referred to as return flow, and act as an important element in the appropriation system in satisfying downstream rights, providing instream flows and delivering water for interstate compacts and equitable apportionment decrees (see the “Agreements, Compacts & Treaties” section for details on Colorado’s downstream obligations). The use of representative historical time periods is typically how the measure and limit of beneficial consumptive use is determined (WEC, 2015). A caveat to this includes transmountain diversions (water exported from a west slope watershed to an east slope watershed), where the imported water is 100 percent consumptive. This means the water can be used to extinction and is not required to provide returns flows, because the water from the diversion will never flow back to its basin of origin (for a more detailed discussion of transmountain diversions, please see the “Agreements, Compacts & Treaties” section).

The definition of beneficial use is purposively flexible to allow for the incorporation of additional uses as new ways of using and delivering water develop, “so long as the need is real, the outcome is productive, and senior water rights are protected,” (Jones & Cech, 2009: 103). While there are others, the following are some of the most common beneficial uses of water rights:

Augmentation Fish & Wildlife Culture Power Generation
Colorado Water Conservation Board Instream Flows & Natural Lake Levels Flood Control Recreation on Reservoirs
Commercial Industrial Recreational In-Channel Diversions
Domestic Irrigation Release from Storage for Boating & Fishing
Dust Suppression Mined Land Reclamation Snowmaking
Evaporation from a Gravel Pit Municipal Stock Watering
Fire Protection Oil & Gas Production Water Storage


By the late 1960s, it was apparent that of the state’s seven major river basins, the South Platte, Rio Grande and Arkansas were overappropriated. A stream or aquifer is considered overappropriated if there is not enough water available to fill new appropriations without causing material injury to existing water rights. The 1969 Water Right Determination and Administration Act included provisions that allow junior uses of water (i.e. environmental, recreational, groundwater, etc.) to operate even if a basin is overappropriated, such as court approval of water exchanges, changes of water rights, augmentation plans, water management plans and substitute supply plans (WEC, 2015).


Every ten years the State Engineer compiles an abandonment list of water rights, as well as a periodic ranking list of active decreed water right priorities. Often referred to as the “lose it or use it” principle, if a water right is not exercised for a consecutive ten year period or more, the right (or a portion of the right) can be presumed abandoned; however, non-use does not necessarily constitute abandonment. Only if the non-use is due to the actual intent of the water right owner to permanently forego the beneficial use of the water can the right be considered abandoned (WEC, 2015; Waskom, et al., 2016). This should not be construed as meaning owners of water rights should always divert their entire decreed amount in order to protect their water right for two main reasons (Waskom et al., 2016):

  1. Colorado Revised Statute 37-92-502(2)(a) explicitly states that taking more water from a stream or aquifer than is needed is considered wasteful and should be curtailed; and
  2. Because the amount of a water right is determined by historical consumptive use, including the amount necessary for diversions, excess diversions will either be discounted as wasteful or made a part of the return flow obligations tied to the water right during a consumptive use analysis. Meetings return flow obligations is often difficult for rights holders, so increasing that obligation will likely be detrimental to the water right holder.

Water rights holders do have the ability to rebut the presumption of abandonment of their right, and do so by documenting intent not to abandon to the State Engineer. Statutes have been enacted allowing for forestalling of abandonment, such as for participating in an approved conservation program, water bank, crop rotational fallowing plan, or loaning the water to the CWCB for instream flow use (WEC, 2015; Waskom et al., 2016). Furthermore, without risking abandonment, municipalities can obtain water for future use based on reasonable population projections over a reasonable water supply planning period. This must be done while taking into account land use combinations and available water conservation measures, and is subject to water court review every six years (WEC, 2015).

Colorado water rights additional resources and references.