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Show DIXIE PROJECT, UTAH 95 arable lands that are readily available in these valleys. The provision of 246,000 acre- feet of storage space at the Virgin City Reservoir on the Virgin River, and 23,745 acre- feet at the lower Gunlock site on the Santa Clara River would provide needed regulation. As a matter of fact, these structures will completely control the available water supplies we have determined are there from our hydrologic studies over a quarter of a century or more. The Hurricane division of the project, embracing the Virgin City Dam and Reservoir, would include all of the project's hydroelectric features, with a total installed generating capacity of 13,200 kilowatts and an irrigation distribution system to serve 17,135 acres of land. It would also provide a municipal and industrial water supply to the city of St. George. Recreation facilities would be constructed at the Virgin City Reservoir, wdiich would be immediately downstream from Zion National Park. The Santa Clara division, including the Lower Gunlock Dam and Reservoir, would furnish irrigation water to 3,925 acres of land and would provide flood control, fish and wildlife, and recreation benefits. In our feasibility investigation, we made sufficient studies and computations" to be sure that, with the Dixie project constructed, the quality of the water for downstream use, although somewhat impaired by project operation, still would be suitable for the irrigation of the salt- tolerant crops now grown in the area. We propose as a part of the advance planning following authorization of the project to thoroughly investigate physical solutions to the water quality problem. Possible solutions would include evaporation of all or part of the flows of the highly mineralized La Verkin Springs, or possibly saline water conversion. A sum of $ 2 million is included in the project cost estimate to provide a physical solution to this problem. We know this is a sufficient estimate because as a maximum solution we could retire the lands nowT being irrigated lower down if the salt problem were acute, for less than $ 2 million - Mr. ROGERS. YOU say $ 2 million Mr. DOMINY. We have $ 2 million in our project estimate- the total estimate that is before the committee for the project cost, for solving this salt problem. Mr. ROGERS. What method is going to be used ? Mr. DOMINY. We don't know. It may be that we can evaporate a part or all of the flow from the La Verkin Springs, which comes in below the dam, and which is the chief contributor to the salt problem in the river. Now, presently, the water is being used for irrigation lower clown for salt- tolerant crops and the spring flows they divert frequently in heavy amounts flush out the salts that accumulate. Now, with project operation, past practices of heavy diversions in the spring will no longer be possible on the same scale because we will be storing some of those waters. Consequently the average salt content of the water being used for irrigation farther down in the Virgin River system may be higher than it has been without the project. That is why we recognize there may be a problem. We may have to do something like evaporating part of this salt or possibly putting in a salt water conversion plant. I merely say that the $ 2 million is such |