Integrating water harvesting and gravity-fed micro-irrigation system for efficient water management in terraced land for growing vegetables

Enhancing and sustaining the productivity of hill agriculture in North-West Himalayan Region (NWHR) is a major challenge as it is practised under ecologically fragile environments which include altitudinal, climatic and topographical variations. The present study envisaged the scope for water resources development and its utilization in crop production through gravity-fed micro-irrigation enhancing water use in the terrace land of NW Himalaya. The water was harvested from a distantly located ultra low discharge water source to the lined tank and the micro-irrigation system (MIS) was integrated such that it could be operated by gravity. The system performance was found satisfactory as the flow rate variation, Christiansen uniformity coefficient and distribution uniformity were 26.5%, 86.3% and 87.5%, respectively. The system saved 41.1% and 33.3% irrigation water as compared to check basin irrigation in case of vegetable pea and French bean, respectively. The water use efficiency of the system was significantly higher than check basin irrigation. Economic indicators such as Net Present Value, Benefit Cost Ratio, Internal Rate of Return and payback period were used to evaluate the gravity-fed MIS and were INR 160,523 (1$ = 40.50 INR), 1.78, 12.2% and 3.38 years, respectively. It is recommended that the gravity-fed MIS must be integrated with the water harvesting system to effectively and economically utilize the water in vegetable cultivation in terraced land of the hill farming system.