WSP05634 - Laserfiche WebLink

Home Browse Search

OOll:..7~ . CHAPl'ER I II ARABLE LANDS Approximately 400,000 acres of arable land are estimated to be lo- cated in the San Juan study area, mostly in the eastern portion. This acreage was estimated by delineating lands that apfeared to be ar- able on 15-minute quadrangle sheets of the Geological Survey. The gross acreage of each area was then reduced by a certain percentage to arrive at an acreage expected to be found arable if a detailed land classifica- tion were rn,de.l/ The Bureau of Indian Affairs participated in estimating arable acreages-in the Navajo Iniian Reservation. Approximately 17,500 acres of the arable land are under irrigation systems bolt only abc>ut 13,000 acres are usually irrigated. Only about 4,000 acres have a full irrigation water s~pply. Approximately 160,000 acres are dry-farmed. The dry farm land is located in the vicinity of Monticello, BlandinG, and La Sal, Utah, ani No~thdale, Colo. . Locations of the land areas are shown on the map on the following page. A tabulation of the arable lan~ acreages by separate areas is shown on page 25. The approximate average annual frost-free perioi above 320 is also sh0Wn in the table for each area. Land drainage characteristics of the Spanish Valley, Bluff, and West Paradox Areas were determined from semidetailei studies made for earlier project investigations. Rough drainage appraisals of other ar- able land areas were made by field inspection. Do loc'es Area The Dolores Area consists of scattered tracts of arable land ex- tending along the lower 45 miles of the Dolores River in Utah and Colo- rado. Also included are lands in Sinbad Valley on Salt Creek and lands along Roc Creek, both tributaries of the Dolores River in Colorado. Data for the Utah and Colorado portions of the Dolores Area are separately tabulatej on page 25. Except for a larger land area in Sinbad Valley, mc>st of the arable lands are in strips 300 to 1,500 feet wide on both sides of the Dolo~es l~ Reduction p~rcentages were based on experience gained from ear- lier land classification s~rveys of sITall parts of the area. These in- cludei surveys m~de for the pc>tential Dolores, San Miguel, and Pack Creek Projects and for lands in the Bluff, Utah, Area. Although land classes W2re determined in these Sl.lrVeys, no atte:npt was ffi:'lde to r-roject ... land classes into the study area as a whole, 23