Status of the Yuma desalting plant

Abstract

The Colorado River is the main source of water for the southwestern United States and northwestern Mexico. Because of increasing consumptive use of the water and increasing return of saline irrigation drainage to the river, the river salinity has steadily increased. The effects are particularly evident at the lower end of the river and consequently in Mexico. The United States has agreed to provide Mexico with water of a salinity of no more than 115p/m greater than the salinity of water arriving at Imperial Dam. Imperial Dam is the last United States irrigation diversion structure on the Colorado River. The United States plans on building a 4.21-m 3/s membrane desalting plant to solve the salinity problem. The plant will be located 7.4 km west of Yuma, Arizona. The current status of the plant can be summarized as follows: The site location has been identified and the land has been purchased; membrane desalting equipment proposals have been received and selection of contractors has been made; specifications for peripheral support equipment such as clarifiers, filters, tanks, recalcining furnaces, and centrifuges will be forthcoming and requests for bidding on these items made; the by-pass drain to the Santa Clara Slough has been completed; the sludge disposal site has been located and methods of sludge disposal determined; and finally, the power source has been identified and power contracts are being prepared. The progress on the plant has been slowed by legal questions concerning the procurement of desalting equipment. A decision by the General Accounting Office on this matter is expected shortly.