Impact assessment of watercourse rehabilitation programs in Sindh, Pakistan using geospatial techniques.

Zaidi, Arjumand Z.; Zafar, Sumaira; Arslan, Muhammad; Malik, Saad; Shah, Sana Ullah; Ullah, Asmat

Pakistan's Indus Basin Irrigation System (IBIS) is one of the world's most extensive contiguous irrigation systems. A considerable challenge for IBIS is conveyance losses through seepages and leaks. About 40% of the water derived from the Indus River is lost while flowing through the watercourses. Two mega projects—the National Program for Improvement of Watercourses (NPIW) and the Sindh On-Farm Water Management Project (SOFWMP)—were initiated in the country to improve the canal system at the watercourse level (tertiary channels). Under these programs, 43,000 watercourses in the province of Sindh were to be improved. This research used geospatial data and techniques to evaluate the watercourses' improvement work under these programs. An increase in the cultivable command areas and water availability at the tail-end after the improvement work have been selected as success indicators. Pakistan Space and Upper Atmospheric Research Commission (SUPARCO) and NPIW provided the locations of the improved watercourses. Hard copies of command area maps were acquired from the Sindh Irrigation departments, digitized, and corrected using satellite images and information gathered during field surveys. Google Earth's images (2004, 2013, and 2021) were utilized for cultivable command areas delineation and their change detection. A substantial expansion in the cultivated land was identified in the command areas of 26 watercourses up to 7.6% (95% confidence interval: 12.5–2.8%). The farmers validated the study results during the field surveys. The farmers and landowners of surveyed watercourses (70%) expressed their satisfaction with the improvement work. They also confirmed water availability at the tail-end and endorsed the study results presenting increased cultivable command areas.

RIVER channels; STREAM restoration; SEEPAGE; WATER supply; CANALS

Arabian Journal of Geosciences, 2022, Vol 15, Issue 21, p1

1866-7511

Academic Journal

10.1007/s12517-022-10904-x