THE PARIA RIVER.
The Paria River rises under the eastern escarpment of the Pauns-a-gunt Plateau, at about the same altitude as Kanab Creek, and flows in a southwesterly course for 100 miles, joining the Colorado in Arizona. Through the greater part of its course the river flows in a deep cañon, but near its head, and at an altitude of 6,000 feet, the cañon expands into a valley. Lower in its course, and at an altitude of 4,500 feet, the cañon again widens into a smaller valley. These are the only areas of arable lands within its drainage basin in Utah. The larger contains 15 and the smaller 10 square miles. In August, 1874, this stream flowed 30 cubic feet per second in the upper valley. The flow in the lower would be one-third greater. High water occurs in April or early in May. At this time the volume is three times greater than in August. Settlements have been made in both valleys, and quite a large area is under cultivation. The soil is excellent.
The critical period in irrigation is the latter part of June or early in July. At this time the stream probably carries 40 feet per second. The land in the lower valley is much subject to flooding from heavy showers that, falling on the table lands and mesas in the upper portion of the drainage basin, pour a torrent often beyond the capacity of the channel to convey through the lower valley. So great was the damage done by these floods in sweeping away dams, breaking through ditches, and inundating the growing crops at the site first selected for settlement, that it was abandoned after three years’ occupation, and other parts, where these sudden rushes could be controlled, selected. Considerable difficulty has been experienced in the lower valley from the vast amount of argillaceous sediment deposited on it. So great during the floods is this deposit from the water used in irrigation that the ground becomes completely coated with an impervious layer, and growing crops, especially of small grains, suffer from the inability of the soil to absorb the water conducted on it. The irrigating capacity of this stream during the critical period could be greatly increased by the construction of reservoirs in which to store the great surplus of water that flows earlier in the season. The cañons above the valleys offer very favorable opportunities for building the necessary dams and embankments.