Laserfiche WebLink
<br />lJu2JJ6 <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />sources, such as transbasin diversions, add water to the system. Development of other <br />sources, such as native flows, decrease river flows. The Colorado program looks at six <br />basic sources of water supply that will be developed to serve new population: <br /> <br />. Native South Platte Flows (Surface and IJndereround)' Generally, new <br />development of South Platte flows will be in wet years during portions of the <br />spring runoff, and will involve surface or underground storage. Development <br />of this source will deplete the river when water is stored, and add water to the <br />river from return flows after use. <br /> <br />. Transmountain Div=ions. Return flows from Colorado River Basin imports <br />enhance South Platte River flows. <br /> <br />. Non-tributary Groundwater. Large amounts of water are withdrawn from the <br />Arapahoe and Larimie-Fox Hills formations of the Denver Basin aquifer. <br />Return flows enhance South Platte River flows. <br /> <br />. Conservation. Conservation will become increasingly important to Front <br />Range municipal water providers. However, conservation will have no net <br />effect on downstream river flows. <br /> <br />. Wastewater Exchanl1'e and Reuse. Water providers who develop non-tributary <br />groundwater and transbasin water supplies have the right to reuse that -water <br />under Colorado law. Although as a practical matter these water providers will <br />never put this water to 100% consinnptive use, reuse and exchange programs <br />will deplete river flows. <br /> <br />. Chanl1'es in Use. As urban demands increase, agricultural land will be taken <br />out of production and irrigation rights transferred to domestic use. Under <br />Colorado law, such changes can be made only if no injury to downstream <br />water rights will result. Generally, the change in use from irrigation to <br />municipal leaves some additional water in the river. <br /> <br />The Colorado program makes assumptions where new population will locate in the Front <br />Range. The program then looks at the sources of water that will likely be developed by <br />major water providers to serve that new population, imposes transit loss factors, and <br />predicts how the development of those sources of supply will, in the aggregate, affect <br />South Platte River flows at the state line. <br /> <br />As new people move to the Front Range, South Platte flows will increase in the fall, <br />winter and spring, and decrease in the swnmer. To mitigate this effect, Colorado will <br />implement new water regulation projects, like the Tamarack project, to shift river flows <br />back to the swnmer period. The size of these projects will be calculated based on new <br />population increases in the Front Range. On an order of magnitude, about 1,800 acre-feet <br /> <br />II <br />