IRRIGABLE LANDS OF THE COLORADO DRAINAGE. 153 
5,000 to 3,500 feet above the sea level. Emerging, it enters the valley of 
the Virgin. This valley is 44 miles in length. Its upper portion is only 
an enlargement of the canon, in which small areas of available land are 
found. Its lower portion is a broader valley, much broken by low, basalt 
covered mesas, and sharp ridges of tilted sedimentary rocks. In the upper 
portion of the valley the river receives several accessions, the principal ones 
being Little Zion, North Fork, “La Verkin, and Ash Creeks. With the 
exception of the Ash, but very little cultivable land is found along these 
creeks. Midway in the valley two streams enter, coming from the Pine 
Valley Mountains and having small areas of irrigable land along their courses, 
and near the foot the Santa Clara River adds its water. The united streams 
leave the valley by a deep canon cut through the Beaver Dam Mountains. 
The valley of the Virgin has a lower altitude than any other portion of Utah, 
and a warmer climate. The soil of the arable lands is usually good, and 
wherever it is possible to irrigate produces abundant crops. Some little 
difficulty is occasionally experienced in the first years of cultivation from 
an excess of alkaline constituents in the soil, but plentiful applications of 
water soon remove this difficulty, and these lands often become the most 
productive. No reliable data concerning the amount of arable land in the 
drainage basin, or the volume of water carried by the Virgin River and its 
tributaries, have been collected. From the best information attainable, the 
amount of land actually irrigated in 1875, is placed at eleven square miles 
This conclusion is based in the main upon returns made in 1875 to the 
Deseret Agricultural and Manufacturing Society, the amount under culti- 
vation in Long Valley having been ascertained by Mr. J. H. Renshawe, of 
this survey. To irrigate this, all the water in most of the tributary streams 
is used, but a large surplus remains in the main river. The amount of arable 
land is far in excess of the water supply, but some considerable expense 
for dams and canals would be necessary to utilize the whole amount. 
It is probable that a portion of the Virgin River can be used to 
advantage below the Beaver Dam Mountains in Nevada, and that a 
sufficient amount to irrigate 25 square miles can be used to good advantage 
in Utah. 
20 AR 
