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~ c..') w Grand Valley Desert Watershed r-- Activity Plan Demonstration Project, Colorado - BlM The Grand Valley Desert Watershed Activity Plan has potential both in total salt reduction (approximately 5,000 tons per year) and transferability to similar saline sites in the Colorado River Basin. BLM lands within the Grand Valley are used for livestock grazing, off-road vehicle use, and target shooting, The area also contains a riparian demonstration project. This plan combines ten grazing allotments (approxi- mately 133,000 acres) with the common objectives of increasing vegetative cover in combination with selected land treatments to reduce salt and sediment yields. In one allotment (M t. Garfield), a three- pasture rest-rotation grazing system with associated range improvements was implemented in 1971. Monitoring data has shown a 33 to 200 percent increase in ground cover. Key species cover increased from 3 percent to 7 percent, The SCS has estimated that site potential for ground cover is between 15 and 20 percent of total cover. Sediment yields, determined from reservoir surveys, showed an associated reduction in sediment yields from 0.5 acre-foot per square mile per year to 0.2 acre-foot per square mile per year. Assuming a 3 percent salt content of soil by weight, this grazing management system potentially reduced salt yields by approximately 14 tons per square mile per year. Allotment manage- ment plans for the remaining nine allot- ments need to be revised or rewritten to incorporate the above findings. Sediment retention structures were constructed in the fall of 1988 to retain sediment and associated salts from off-road vehicle use. The effectiveness of these structures is currently being monitored, The East Salt Wash Riparian Demonstration Project is located within the Grand Valley Desert Watershed Activity Plan area, Salinity control options associated with riparian improvements are currently being monitored. Las Vegas Wash Unit, Nevada - Reclamation The Lower Colorado Region has a con- tinuing monitoring program of the Las Vegas Wash Unit. This activity consists of quarterly collecting and analyzing water samples from selected locations in the Wash, Water quality data will be evaluated and reported annually to permit identifi- cation and tracking of any trends in water quali ty. lower Gunnison Basin, Colorado Reclamation Winter Water.-Under the cooperative agreement with the Uncompahgre Valley Water Users Association, Reclamation has obtained an inventory of the water system needs for the Winter Water portion of the project. One of three water suppliers is expected to be ready for construction in fiscal year 1990. The Appropriations bill for energy and water development (including Reclamation) for fiscal year 1990 includes $2.5 million for initiating construction activities in the Winter Water portion of the Lower Gunnison Basin Unit. North Fork area.-In the North Fork area, Reclamation has not found a viable plan and a Preliminary Findings Report concluding the study was published in December 1989. 7