Hydraulic performance on buried pipe irrigation systems

Abstract

Hydraulic tests were conducted for buried pipe system in eight different locations with buried non-reinforccd concrete pipe to distribute water from deep tubewclls irrigating diversified crops. Average pump and outlet discharges were found 58% and 49%, respectively of the design rate (56 I/s). Average deep tubewell efficiency was 69%. There were significant variations in water losses from scheme to scheme. The variations ranged from 5.88 to 937 I/s/100 m for earthen channel length by Inflow-outflow method whereas the water losses from buried pipeline varied from 0.35 to 1.44 l/s/100 m. However, by tank test method, the water loss from buried pipe systems varied from 0.10 to 1.18 l/s/100 m. Leakage through joints and pipe walls was 0.7 leaks per 100 m of pipeline. Using buried pipe systems 81% of pumped water can be delivered more efficiently throughout the command area and this system also saved 91% irrigation water compared to earthen open channel systems. Measured head losses for different pipe sizes and pump discharges were found comparable with theoretical values.