Senate Joint Resolution 94-32 Concerning the Management, Conservation, and Preservation of Water Resources of CO

Home Browse Search

and for longer periods during drought years. Thus, there is potential to consume additional water in the South Platte River Basin if constraints resulting from the Endangered Species Act can be addressed through the implementation of a basin -wide recovery plan. This recovery plan is now under negotiation pursuant to a June, 1994 Memorandum of Agreement between the Secretary of Interior, Governor Romer and the Governors of Nebraska and Wyoming. Figure 1.1 shows the seven irrigation water divisions of the state, major streams, and the historic average annual stream flows (USGS Water Resources Data, Colorado). As of 1993, more than 10 million acre -feet of water leave the state in an average year. Of that amount, approximately 87 % (9.097 million acre -feet) flows west from the Continental Divide toward the Pacific Ocean and 13 % (1.337 million acre -feet) flows east toward the Atlantic Ocean. The location of the state's water supply is in direct contrast to the location of consumptive use in the state, with approximately 25 % located west of the Continental Divide and 75 % located east. The difference in location between water supply and demand has resulted in the development of 24 transmountain diversions within the state. (See Figure 1.2). Figure 1.3 shows a typical hydrograph for two rivers in the state that are not significantly impacted by upstream storage. As presented, approximately two- thirds of the runoff occurs over one - quarter of the year. The seasonal timing of runoff has resulted in the development of many surface reservoirs to capture the spring runoff for use later in the year. Table 1.3 summarizes the total decreed absolute and conditional water rights in the state by Water Division as of 1990. It clearly shows the magnitude and importance of reservoir storage to manage the significant variances of runoff to better meet the demands of the users. As of 1990, a total of 8,747,632 acre -feet of reservoir storage had been constructed and decreed by the court as absolute water rights. (Absolute water rights are those that have been placed to beneficial use. Conditional water rights are decreed, but will be placed to beneficial use at some future date, i.e., through development of the specific project). Finally, Colorado law, which includes interstate compacts, governs the allocation and administration of water rights in the state. Within Colorado, water is distributed according to the prior appropriation doctrine. A comparison of Figure 1.1 with Table 1.3 clearly suggests that if all conditional rights were to be developed, unappropriated water would not exist in the state. Furthermore, such future development would often need to be curtailed in order to meet the state's compact obligations.