|
acre-feet per year. According to the State's geographical information system (GIS) records, total
<br />irrigated acreage in the basin (based on 1993 imagery) was approximately 271,000 acres. Irrigated
<br />acreage dropped slightly to about 230,000 acres in 2000.
<br />Another major water use in the Upper Colorado River is transmountain diversions. These diversions
<br />serve water supply needs for irrigation and municipal uses along the Front Range and eastern plains
<br />of Colorado. Major transmountain diversions and the average amount diverted over the model
<br />calibration period 1975-2005 are as follows:
<br />• Colorado-Big Thompson (CBT) Project exported approximately 232,000 acre-feet per year
<br />via the Alva B. Adams Tunnel for irrigation and municipal use in northern and eastern
<br />Colorado,
<br />• City of Denver's Moffat Tunnel System diverted over 57,000 acre-feet per year,
<br />• City of Denver's Roberts Tunnel System diverted approximately 58,600 acre-feet per year,
<br />• Fryingpan-Arkansas Project exported approximately 51,000 acre-feet per year for irrigation
<br />and municipal use in southeastern Colorado,
<br />• Independence Pass Transmountain Diversion System diverted approximately 38,500 acre-
<br />feetper year for municipal, industrial, and irrigation uses primarily in the Arkansas River
<br />basin,
<br />• Homestake Diversion Project diverted approximately 24,000 acre-feet per year from the
<br />Upper Eagle River tributaries for municipal use in Colorado Springs and Aurora.
<br />Other major water uses in the Upper Colorado River basin include power generation, industrial,
<br />municipal, and transbasin diversions within the basin. Principal power generation diverters include
<br />Shoshone Power Station, Grand Valley Power Plant, and Molina Power Plant, with collective
<br />historical diversions of approximately 1,064,000 acre-feet per year. Mining operations and
<br />snowmaking constitute the remaining major industrial uses in this basin. Diversions for municipal
<br />use include large population centers, municipal districts (i.e. Ute Water Conservancy District), and
<br />numerous small towns.
<br />In addition to direct ditch diversions, there are 20 operational reservoirs in the model, including three
<br />that represent aggregations of numerous small facilities on Grand Mesa. Four reservoirs, including
<br />Rifle Gap Reservoir, Harvey Gap Reservoir, Vega Reservoir, and Leon Creek Aggregated Reservoir,
<br />are used primarily for irrigation. Six reservoirs, including Shadow Mountain/Grand Lake (modeled
<br />as one storage facility), Granby Reservoir, Willow Creek Reservoir, Meadow Creek Reservoir,
<br />Homestake Reservoir, and Upper Blue Reservoir, are predominantly used to store water for
<br />transmountain diversions. Bonham Aggregated Reservoir and Cottonwood Aggregated Reservoir
<br />serve industrial uses. The remaining reservoirs, including Williams Fork Reservoir, Green Mountain
<br />Reservoir, Dillon Reservoir, Clinton Gulch Reservoir, Ruedi Reservoir, and Wolford Mountain
<br />Reservoir, serve multiple uses, including municipal, industrial, irrigation, recreation, and endangered
<br />fish instream flows. With the exceptions of Meadow Creek Reservoir (1975), Clinton Gulch
<br />Reservoir (1977) and Wolford Mountain Reservoir (1995), all the above reservoirs were constructed
<br />prior to the 1975-2005 water year calibration period. Wolcott Reservoir and Eagle Park Reservoir
<br />are included in the model but only as placeholders for additional future scenarios. Three of these
<br />reservoirs are below the 4,000 acre-feet cutoff for inclusion in the model. However, Upper Blue
<br />Upper Colorado River Basin Information 1-2
<br />
|