CRBSCP - McElmo Creek Unit - Title II
The total irrigation diversion into the area averages 105,200 acre feet per year. The average salt load contributed by the McElmo Creek Basin was estimated at 119,000 tons per year. The Montezuma Valley Irrigation Company diverts water from the Dolores River to serve irrigation in the McElmo Creek Basin. The salinity of the diversion averages 130 mg/L. Return flows from agriculture increase the salinity in McElmo Creek to about 2,600 mg/L at the ColoradoUtah State line. The McElmo Creek Basin is located in southwestern Colorado and covers approximately 720 square miles. About 150 square miles of the basin, mostly in the east, are agricultural land. Early studies show that salt-loading results from both irrigation and diffuse sources. Irrigation is the main contributor.
Through these actions, Reclamation and the U.S. Department of Agriculture have improved the irrigated areas so that they produce more crops and use less water. The 1999 Progress Report estimates that the McElmo Creek Unit in the Dolores project removes 23,000 tons of salt per year, for a total capital cost of $44,700,000 and an annual O&M cost of $33,000--for a cost of $160 per ton.
Reclamation.-- Reclamation lined laterals and constructed the Towaoc Canal to control seepage.Buried pipe laterals have been brought down from the Towaoc Canal to serve areas once served by the now abandoned Rocky Ford Ditch. These actions reduce groundwater seepage from canals by 4,060 acre feet a year and reduce the amount of salt returned to McElmo Creek. USDA-The McElmo Creek USDA salinity control report was published in 1983, with the final environmental impact statement released in 1989. The recommended plan calls for treatment of about 21,550 acres with sprinkler irrigation systems and about 270 miles of onfarm ditch and lateral lining. Implementation of the USDA program has been underway in this area since 1990. The major salinity reduction practices being installed are side-roll sprinkler systems, underground pipelines, and gated pipe. A fully coordinated implementation effort is underway, so design and installation of the laterals by Reclamation complement the onfarm irrigation systems. Joint planning actions with Reclamation have made it possible to install gravity pressure sprinkler systems on an additional 9,000 acres.