|
<br />c..J
<br />Q
<br />...
<br />-..t
<br />
<br />cooperation with the University of Wyoming. This
<br />pilot operation wili supply needed information
<br />regarding the capability of freezing, effectiveness of the
<br />sprinkler equipment and configuration for best ice
<br />formation, the amount of salt that can be removed,
<br />quality of the product water, cost per ton of salt
<br />removal, and environmental impact of the process. A
<br />feasibility report is scheduled for fiscal year 1978.
<br />
<br />McELMO CREEK UNIT, COLORADO
<br />
<br />McElmo Creek is tributary to the San Juan River near
<br />the Colorado-Utah State line, Although the drainage
<br />area is only 350 square miles, the salt loading is
<br />estimated to be 130,000 tons per year of which about
<br />40,000 tons could be removed by selective withdrawal
<br />and evaporation or desalting. The resulting effect at
<br />Imperial Dam is a concentration decrease of about 4
<br />mg/I.
<br />
<br />Data collection began in 1972 and includes
<br />measurements that will identify the magnitude and
<br />effects of return flows from the irrigated areas near
<br />Cortez. Recently, consideration of mitigation measures
<br />for the Dolores Project has led to the investigation of a
<br />possible impoundment and evaporation of Mud Creek,
<br />a tributary of McElmo Creek. Feasibility studies for
<br />McElmo Creek Unit are to be completed in fiscal year
<br />1978.
<br />
<br />PRICE, SAN RAFAEL, AND DIRTY DEVIL
<br />RIVER UNITS, UTAH
<br />
<br />The Price, San Rafael, and Dirty Devil Rivers originate
<br />in the mountains of the Wasatch and Aquarius Plateaus
<br />and are tributary to the Green and Colorado Rivers in
<br />east~central Utah. Drainage areas contain 1,500, 1,670,
<br />and 4,200 square miles for the Price, San Rafael, and
<br />Dirty Devil Rivers, respectively. The estimated total
<br />dissolved solids contributed by the Price, San Rafael,
<br />and Dirty Devil Rivers are 240,000. 210,000, and
<br />200,000 tons, respectively,
<br />
<br />The estimated annual removal of salt by proposed
<br />control programs are 100,000 tons on the Price River
<br />and 80,000 tons each for the San Rafael and Dirty
<br />Devil Rivers. Salinity concentrations of the Colorado
<br />River at Imperial Dam would be reduced by an
<br />estimated 9 mg/I for the Price River and 7 mg/I for
<br />each of the San Rafael and Dirty Devil Rivers.
<br />
<br />Investigations thus far have included field surveys, data
<br />gathering, and tentative formulation of oontrol plans to
<br />remove the concentrated flows from these streams.
<br />
<br />Feasibility reports are scheduled for fiscal year 1978.
<br />
<br />UTILIZING RETURN FLOWS
<br />
<br />
<br />The potential of treating or converting irrigation return
<br />flows to other beneficial consumptive uses such as
<br />thermal powerplant cooling and coal gasification
<br />within the basin to avoid returning them to the river
<br />system is being examined. The San Juan area will be
<br />studied in FY 1974 and 1975 to be followed by the
<br />Grand Valley area in 1976 and 1977, Utilization of
<br />return flews will be investigated in the lower main stem
<br />during the fiscal 1974,78 period,
<br />
<br />RESEARCH
<br />
<br />Research is underway on onfarm irrigation efficiencies,
<br />desalting by natural freezing, and modeling for
<br />predicting salt and nutrient loading. A cooperative
<br />program with the Agricultural Research Service is
<br />underway in the Grand Valley area to determine the
<br />optimal irrigation water application rates to maintain
<br />crop yields while reducing salt-laden return flows.
<br />
<br />Con s iderable other salinity research has been
<br />stimulated by the CRWQIP, This research is providing
<br />inputs to the program but is being funded through
<br />other sources. The Western Directors of the
<br />Agricultural Experiment Stations have established a
<br />regional research project entitled "Salinity
<br />Management in the Colorado River Basin." This will
<br />involve cooperation with the USDA. The research is
<br />aimed at developing and evaluating methods for
<br />understanding and managing salinity from agricultural
<br />and diffuse natural sources in the Colorado River
<br />Ba~in.
<br />
<br />The Office of Water Resources Research (OWRR) is
<br />also sponsoring a regional research project on salinity.
<br />Through OWRR, several Colorado River Basin States
<br />Water Resources Research Institutes are investigating
<br />the economic aspects of salinity control. The research
<br />is directed toward evaluating damages caused by
<br />salinity. The Bureau of Reclamation is participating
<br />and cooperating in the research effort.
<br />
<br />A special study has been completed of the potential
<br />application of ion exchange desalting to the total flow
<br />of the Colorado River System. The intent of this study
<br />was to determine the possibilities of controlling salinity
<br />at the diversion point from the river rather than at its
<br />source. The study was supported by a 6-week
<br />operation of an ion exchange pilot plant on the
<br />Colorado River below Davis Dam. The 5,000,gpd plant
<br />successfully reduced 750 ppm water to 550 ppm
<br />product water. Future studies will concentrate on
<br />smaller installations having plant capacities similar to
<br />the present major diversions. A report covering this
<br />study was completed in 1972,
<br />
<br />11
<br />
|