Laserfiche WebLink
<br /> <br /> <br />Colorado Rrver Basin SallnJTy conrrol Proqram <br /> <br /> <br />t' <br />CJ' <br />r..r~ <br /> <br />San Juan River Unit <br /> <br />.:.. ~ <br /> <br />Reclamation-The San Juan River Unit area IOcludes the enure 23.()(X)-square-mile watershed <br />from Its headwaters in south-centul Colorado to Its mouth at Lake Powell. The drainage <br />contributes approx.imately 1 million tons of salt annually to me Colorado River Basin. Early <br />reconnaIssance shows sigruflcaOl salt loading in the ri\-er between Shiprock. New Mex.ico. and the <br />Four Comers area. At Bluff. Utah. the annual now of 2.047.000 acre-feet of water contains <br />1.165.000 tons of salt. About 18 percent of thiS salt loadmg occurs between Shiprock and Bluff. <br />but only 7 percent of the water is added 10 this reach. <br /> <br />The Hammond Project. Navajo Indian Irrigation Project (NIIP). and the Hogback. Irrigation Project <br />/also a Navajo Indian project) are the prinCipal irnganon sources of salt m the San Juan River <br />Basin. Reclamation has focused Its planning effortS In the San Juan River Unit by preparmg a <br />planning reportJenvirorunental assessment for the Hammond area. A fmal report and fmding of no <br />)lgmficant Impact v. as published 10 December 1994. <br /> <br />The Hanunond Project was awarded a contracllate in 1996 under Reclamation's Basinwide Salinity <br />Control Program. The project will replace unlined canals and laterals which are extremely leak)" <br />due to sandy soils, The project is bemg constructed by the local water district. Reclamation was <br />retained by the dIstrict to design the faCIlities. The dIstrict awarded a contract and construction <br />staned in FY98. Two miles of unlined laterals have been placed 10 concrete using a slip form <br />purchased. b)' the district. An addItional 10 miles of hmng are scheduled for 1999. <br /> <br />The district has hIred an environmental consultant to begin compliance work to Implement me <br />en\'ironmemal commitments contained 10 the environmental assessment. They have also conducted <br />sur...eys With F\\'S for the southwestern willow flycatcher. So birds were found in the project <br />area f\,\'S IS working With the consultant to develop wildlife habitat replacemem plans for the <br />district <br /> <br />l'SDA-Sallnity investigations were completed by USDA in the San Juan Ri\'er Basin east of the <br />Hogback It was delermmed that 3. USD.A. onfarm saiLnir)' comrol program is not feasible in this <br />area In 1991. In\'e!>tigalions were mluated in the San Juan RIver Basin west of the Hogback to <br />determme if an onfarm program might be feasible. The study area lies within the boundaries of the <br />~avajo Indian ~ation, This study was completed in 1993. The repon recommended that funher <br />study be done in the area. <br /> <br />Selenium Studies <br /> <br />Selenium is a relatively minor component of the total dissolved solids (salmity) found in the <br />Colorado Ri\'er. but it has been found to have a significant impact on wildlife (birds and fiSh), <br />High salinit)' and selenium le\'els are often associated With marine shales and saline soils. Studies <br />are underv.:ay to detemune if saliM)' control might also help control selenium loading. <br /> <br />59 <br />