PUB00055 - Laserfiche WebLink

Home Browse Search

Two types of water rights are recognized in colorado. There are diversion rights, to be put to beneficial use without storage, which are available whenever streamflow exceeds the demands of prior appropriations: and there are storage rights that usually permit one reservoir filling per year, providing prior appropri- ations are satisfied. Appropriation of water is not completed until the diversion or storage structure is completed and water is put to beneficial use. In 1939, the Supreme Court of Colorado recognized the right of municipalities to appropriate water for the needs resulting from a normal increase in population within a reasonable time in the future and to lease the use of surplus water pending its need by the city. The earliest appropriations of water in Colorado date to 1852 and were for irrigation. In the south Platte River basin, most streamflow usable without storage had been appropriated by the 1880's and by about 1910 most feasible storage rights had been developed, largely for irrigation. Cities and towns in the south platte River basin were unable to appropriate water prior to 1910 sufficient for the urban population of 1960, which is about 3~ times greater than it was in 1910. The greatly in- creased municipal needs on the eastern slope of the Rocky Moun- tains have had to be filled either by purchase of senior rights or by transmountain diversions from underappropriated streams in the Colorado River basin. on the eastern slope of the Rocky Mountains, appropriations for reserve supplies of water for future urban growth are limited and transmountain diversions are reaching the limits of presently accepted standards of feasibility. Only in the Colorado River basin are surplus surface-water supplies to be found within the State. One aspect of urban growth, however, tends to alleviate the overall water shortage. When previously irrigated farm lands in Colorado are urbanized, water consumption per unit area is de- creased. For example, the Denver Water Board in 1959 delivered water equivalent to a depth of about 2 feet for the area served: consumptive use is estimated to have been less than 1 foot, whereas consumptive use on irrigated lands in the South platte Valley is estimated to be between l~ and 2 feet annually. Several cities in northeastern Colorado require that when surrounding irrigated lands are subdivided they must cede their original water rights to the city in order to receive municipal water service. Better treatment of municipal return flow could also amel- iorate the overall water-use problem. Presently, the amount diverted is charged against the user's water right, regardless of the amount returned again to streamflow. It is estimated that many municipalities return, as sewage, about half the amount of water they divert. Modern techniques of sewage treatment en- able cities to make this return flow acceptable for practically any further use. Credit for returning acceptable water to stream- flow would provide more incentive to improve treatment facilities. 15