Gunnison_BasinReport_200407 - Laserfiche WebLink

1.2. Human and Economic Factors The first permanent populations of white settlers came to the upper Gunnison basin in the 1800s to mine for silver. With the exception of continued mining of coal in the basin, the mineral industry is no longer a key economic sector. Farming and ranching, as well as recreation and tourism, are the primary activities in the basin today. The area remains relatively sparsely populated, with the 2001 census estimates placing the combined populations of Gunnison, Delta, and Ouray Counties at approximately 46,250. Montrose and Delta are the major population centers in the basin, with approximately 12,300 and 6,400 residents respectively. Gunnison and Delta Counties grew by just over 30 percent from 1990 to 2000, and Ouray County grew by over 60 percent in the same time period. Growth is concentrated in the lower Gunnison Valley near Grand Junction and along the Uncompahgre River near Montrose. This growth attests to the importance of recreation-based activities, as the ski area and other outdoor recreation opportunities draw people to the basin and increase tourism within the basin. Tourism serves as an important part of the basin's economy. Much of the upper basin is predominately forest and rangeland, with irrigation becoming the principle consumptive use of water in the lower Gunnison basin. Irrigation is used for various crops including pasture, hay, fruit, corn, alfalfa, and small grains. The total irrigated acreage in the basin is estimated to be approximately 336,000 acres for the year 2000, according to the Colorado Water Conservation Board (CWCB). While diversions from many of the small irrigation ditches average one or two thousand acre-feet per year, the Gunnison Tunnel diverts approximately 320,000 acre- feetper year to supply large irrigators in the Uncompahgre River Basin. Primary use of surface water throughout the entire basin is for hydropower generation, which has historically diverted over approximately 3 million acre-feet per year, according to the CWCB. Note that this use is non-consumptive. The Aspinall Unit of the Colorado River Storage Project encompasses the major power plants within the basin. Hydroelectric power plants are located in series at the dams of the Blue Mesa, Morrow Point, and Crystal reservoirs. The three power plants have the capability to generate up to 208,000 kilowatts of power for the basin and surrounding areas. There are also diversions for municipal and industrial use in Delta and Montrose, as well as in a number of smaller towns. One major transbasin diversion, the Redlands Canal, exports water from the Gunnison River basin to the Colorado Mainstem basin. The diversion's senior water rights account for 750 cfs, which can be used for irrigation and power generation. There are also a number of smaller transbasin diversions from one tributary drainage basin to another. In addition to the direct ditch diversions, there are eleven major reservoirs (greater than 4,000 acre- feet in capacity) in the Gunnison River basin. Three of the largest reservoirs, Blue Mesa, Morrow Point, and Crystal, were constructed pursuant to the Colorado River Storage Project, which was enacted in 1956. The reservoirs, with normal capacities of 940,800 acre-feet, 117,190 acre-feet, and 26,000 acre-feet respectively, were constructed to normalize and maintain the delivery of Colorado River Compact water to the lower basin in years of limited precipitation. Two reservoirs, Taylor Park and Ridgway, are predominately used to store water for supplemental irrigation water supply and release for fish flows. The remaining reservoirs include Paonia, Crawford, Silverjack, Gould, Overland, and Fruitgrowers Reservoirs, which are predominantly used for irrigation. Gunnison River Basin Information 1-2