The San Juan River Unit is in northwestern New Mexico along the southern banks of the San Juan River opposite the towns of Blanco, Bloomfield, and Farmington, New Mexico. The watershed is 23,000-square-miles from its headwaters in south-central Colorado to its mouth at Lake Powell. Drainage from this watershed contributes approximately 1 million tons of salt annually to the Colorado River Basin. Early reconnaissance shows significant salt loading in the river between Shiprock, New Mexico, and the Four Corners area. At Bluff, Utah, the annual flow of 2,047,000 acre-feet of water contains 1,165,000 tons of salt. About 18 percent of this salt loading occurs between Shiprock and Bluff, but only 7 percent of the water is added in this reach. The existing Hammond Project, an irrigation project in San Juan County, New Mexico contributes salt to the San Juan River, a major tributary of the Colorado River. The project area is underlain by, or lies adjacent to the San Jose, the Nacimiento, the Ojo Alamo, and Kirtland Formations. The soil in the area is composed primarily of moderately saline shales and sandstones. The Navajo Indian Irrigation Project (NIIP), and the Hogback Irrigation Project (a Navajo Indian project) are also irrigation sources of salt in the San Juan River Basin. Water seeps from unlined water conveyance systems and flows toward the river through the alluvium and along the bedrock, where it picks up the soluble salt. The viable solution to this problem is to line the project`s unlined canals and laterals. Reclamation has focused its planning efforts in the San Juan River Unit by preparing a planning report/environmental assessment for the Hammond Project. A final report on the Hammond Salinity Control Project was published in December 1994.
The Project was included in a comprehensive water quality study of the Colorado River drainage called the Colorado River Water Quality Improvement Program (CRWQIP). The Reclamation December 1994 Planning Report, the `San Juan River Unit Hammond Project Portion, New Mexico` concluded that at least 27,700 tons to as much as 68,560 tons of salt could be removed from the San Juan River by lining the remaining 26.7 miles of unlined canals and laterals to reduce seepage losses. http://www.usbr.gov/dataweb/html/basinwidescp.html
The Hammond Salinity Control Project was awarded a contract late in 1996 under Reclamation`s Basinwide Salinity Control Program. The project will replace unlined canals and laterals which are extremely leaky due to sandy soils. The project is being constructed by the local water district. Reclamation was retained by the district to design the facilities. The District has a contract agreement with Evans Engineering, Inc. of Bloomfield NM for preconstruction work and overall construction management. Environmental mitigation is being handled under a contract with Taschek Environmental Services of Albuquerque, NM. The district awarded a contract and construction started in FY98. Two miles of unlined laterals have been placed in concrete using a slip form purchased by the district. Construction on the conveyance systems occurs between the months of October to mid April to avoid disturbances to the irrigation season. In the off season of 1997-1998, approximately 2.1 miles of the East Highline Lateral was completed. In the 1998-1999 season, 0.5 miles of the West Highline Lateral, 3.3 miles of the Gravity Extension Lateral and approximately 4.7 miles of the Main Canal were completed. In the off season of 1999-2000, an estimated 9.3 miles of the Main Canal will be under construction as well as portions of the project mitigation. The remaining portion of the Main Canal, a small section of the West Highline Lateral and remaining project mitigation will be completed in the season of 2000-2001.