Use of numerical modelling for management of canal irrigation water

✍ Scribed by Abdul Razzaq Ghumman; Muhammad Zubair Khan; Muhammad Jamal Khan

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 168 KB
• Volume: 55
• Category: Article
• ISSN: 1531-0353
• DOI: 10.1002/ird.265

✦ Synopsis

Flow regulation and distribution structures play an important role in the overall management of irrigation canals. In this paper the solution of one-dimensional Saint Venant equations of continuity and momentum was applied to a secondary canal in the Abazai Branch of the Upper Swat Canal Irrigation System, North West Frontier Province of Pakistan. The system has been changed from supply based to crop based. The aim of the study was to firstly evaluate the performance of canal outlets under different discharge conditions. The second aim was to assess the response of any modifications in the dimensions of the canal outlets on water distribution under different discharges. Five cases of 100, 80, 70 and 50% of design discharge were tested. The additional operational option of opening and closure of the canal was also evaluated. It was found that under the existing configuration of the canal, the majority of the canal outlets were not drawing discharges according to their allocations for all the four discharge levels. Modifications in outlet dimensions improved the outlet performance. The best performance of canal outlets was obtained under 100 and 80% of the design canal discharge after modifications. In the periods of low irrigation demand, the study recommends opening and closure of the canal instead of operation at lower than 80% of design discharge.