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Show WATER FOR UTAH TABLE 16 PRESENT AND POTENTIAL ANNUAL REQUIREMENTS AND USE OF WATER FOR IRRIGATION IN THE GREEN RIVER DRAINAGE BASIN, UTAH Item Area Required for Full Supply Present Water Supply Additional Water Planned Within Basin Coloradc Basin Shortage After Proposed Development Adequacy of Supply After Development Land with adequate supply Land with inadequate supply: No additional water proposed Additional water proposed New lands.. Total used and proposed for irrigation Total arable lands 1,000 acres 61.7 25.2 145.0 141.3 373.2 466.6 1,000 A.- Ft. 118.3 45.8 244.0 230.0 638.1 816.6 1,000 A.- Ft. 118.3 35.2 209.0 362.5 362.5 1,000 A.- Ft. 1,000 A.- Ft. 35.0 230.0 265.0 265.0 1,000 A.- Ft. 10.6 10.6 189.1 Per cent 100.0 76.8 100.0 100.0 98.3 76.8 and Kane Counties and smaller parts of Sevier and Emery Counties. In all, it has an area of about 12.5 million acres. The area is generally a high, mountainous plateau, so rough and broken that parts of it are almost inaccessible. The Colorado River traverses a deep gorge much of the way, and its waters are generally not available for irrigation. Only the tributaries can be used for this purpose on the upper reaches. The main tributaries are the Fremont and Es- calante Rivers from the west and the San Juan River from the east. The total storage in this area is less than 20,000 acre- feet, most of which is on the headwaters of the Fremont and Esca- lante Rivers. Very little use can be made of the waters of the San Juan. ... Present Irrigation Development... Although the area of this drainage basin is large, the total irrigated area is only 45,800 acres, and of this only 4,200 acres have an adequate water supply. The other 41,600 acres have only 75.2% of a ful! supply. The total known arable land amounts to only 260,200 acres, but less than 20% of this is irrigated. The developed water supply is less than 15% of the amount needed to irrigate adequately all the soil that is suitable for irrigation. There is some dry farming, but relative to the total area, it is not large. ( See Table 17.) TABLE 17 PRESENT ANNUAL REQUIREMENTS AND USE OF WATER FOR IRRIGATION IN THE COLORADO RIVER DRAINAGE BASIN, UTAH Present Water Supply Area Water Required for Adequate Supply Present Supply Present Shortage Present With Adequate Supply Adequate.. Inadequate Total irrigated Potential arable 1,000 acres 4.2 41.6 45.8 260.2 1,000 A.- Ft. 8.0 96.3 104.3 546.4 1,000 A.- Ft. 8.0 72.4 80.4 80.4 1,000 A.- Ft. 23.9 23.9 466.0 Per cent 100.0 75.21 77.11 14.7 1Often the effective supply is less than this because the shortage is concentrated in the latter part of the growing season. LI201 |