Effect of Watercourse Aging on Conveyance Efficiency and Water Productivity in District Muzaffarabad, Azad Jammu and Kashmir
Effect of Watercourse Aging on Conveyance Efficiency and Water Productivity in District Muzaffarabad, Azad Jammu and Kashmir
Raja Waqar Ahmed Azad, Tahir Sarwar
ABSTRACT
A field study was conducted to assess the ageing effect of Plain Cement Concrete (PCC) lined watercourses on conveyance losses/efficiency in district Muzaffarabad, Azad Jammu and Kash- mir. Three watercourses namely, Sarai, Derkot and Mera Dadu were selected randomly on aging basis. Watercourses Sarai, Derkot and Mera Dadu were constructed in 2000, 2006-07 and 2011, respectively. Conveyance losses in the selected watercourses were determined by inflow-outflow method, wherein the flow velocity was measured using current meter. The conveyance losses were found 13.2%, 11.8% and 7.8% in watercourses Sarai, Derkot and Mera Dadu, respectively, which resulted in conveyance efficiency of 86.8%, 88.1% and 92.4%, respectively. Results showed that conveyance losses increased and conveyance efficiency decreased with the aging of watercourse. Hence, more repair and maintenance is required for aged watercourses to minimize conveyance losses. Water productivity and water management practices were computed from field observations and farmers’ interviews. Water productivity of rice in the command area of selected watercourses ranged from 0.15-0.23 kgm-3 with average value of 0.19 kgm-3, water productivity of wheat ranged from 0.77-1.48 kgm-3 with average of 1.18 kgm-3, water productivity of maize ranged from 0.68-1.25 kgm-3 with average of 0.90 kgm-3 and average water productivity of onion crop ranged from 0.29-0.36 kgm-3, with average of 0.32 kgm-3. Water productivity of onion was lower compared to the values reported by FAO and others. Better watercourse maintenance and irrigation management practices were found in watercourse Sarai, whereas, watercourse Derkot had poor watercourse maintenance and field practices. Results showed that crop yields were higher in watercourses having good water management practices. It can be concluded that aging of watercourses increase conveyance losses, which can be offset by regular repair and maintenance of watercourses.
To share on other social networks, click on any share button. What are these?
