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INTRODUCTION o ~ Increasing salinity is threatening to become a major economic problem for users of Colorado W River Water [Kleinman and Brown, 1980]. This basinwide problem affects more than 18 million municipal, agricultural, and industrial users in the lower Colorado River basin as well as the Republic of Mexico. In 1988 it was estimated that the total annual salinity damages from the use of Colorado River water in the lower Colorado River basin had reached about $300 million; damages are expected to reach $900 million per year by the year 2010 [Lohman, et aI. 1988]. Damages to agricultural users are in the form of reduced crop yields, added labor costs for irrigation management, and added drainage requirements, Urban users incur additional costs due to more frequent replacement of plumbing and water-using appliances, use of water softeners, and the purchase of bottled water. Industrial users and water treatment and waste water utilities incur reductions in the useful life of system facilities and equipment from increased levels of salinity [Colorado River Basin Salinity Forum, 1990]. The Colorado River Basin Salinity Control Act of 1984, as amended (Public Law 98-569); the Clean Water Act of 1987 (p.L. 100-4); the Water Resources Planning Act of 1983, as amended (p,L. 97-449); and Executive Order 12088 ("Federal Compliance With Pollution Control Standards") as amended by Executive Order 12580, all provide direction for reducing nonpoint source pollution (salinity) to the Colorado River System from public lands. The Grand Resource Area Resource Management Plan identifies control of salinity and sedimentation of the Colorado River from public lands as the Critical Watershed issue in the Grand Resource Area, Moab District, Bureau of Land Management (ELM). Salinity control, as reflected in the management actions of the RMP, involves two options: (1) the use of mechanical treatments to stimulate restoration of degraded areas and control runoff and sediment production and (2) management of resource activities that disturb the soil surface, In 1985 the Greater Sagers Wash Watershed was identified as one of the major salt producing watersheds in the Moab District. The Greater Sagers Wash Watershed is an area of approximately 153,200 acres located 5 miles east of Thompson, Utah, within the Grand Resource Area, Moab District, BLM. (See Figure 1.0). The watershed has its headwaters in the Book Cliffs at an elevation of about 9,000 feet and empties into the Colorado River approximately 32 miles to the southeast at McGraw Bottom, at an elevation of about 4,100 feet. Approximately 60 percent of the watershed is characterized by Mancos Shale-derived saline- alkali soils which are naturally high salt producers. The majority of the watershed is characterized by sparse vegetation cover, high rates of erosion, and high peak flows. Erosion, sedimentation, and salt yield in the Greater Sagers Wash Watershed are primarily the result of two processes; natural geologic erosion, and accelerated erosion. Natural geologic erosion originates from naturally occurring Badlands and rock outcrop formations. (See Table 1