Sediment transport by irrigation return flows on the Yakima Indian Reservation, Washington 1975 and 1976 irrigation seasons

As determined from data collected at 10 sites on the Yakima Indian Reservation during the 1975 and 1976 irrigation seasons (April-September), seasonal sediment discharges in irrigation return flows ranged from 11,000 tons from Marion Drain and Satus Drain 302, to 400 tons from Coulee Drain. There was little variation between the sediment discharges of the 1975 and 1976 irrigation seasons except those from Satus Drain 302. Due to the lack of natural runoff during those seasons, no distinction could be made between sediment discharges from irrigated and nonirrigated areas. No significant or usable relationships were found between suspended-sediment concentration and concurrent water turbidity or discharge.