On-Farm Balancing Reservoir Design on the Basis of Canal W ater A vailability and Gr ound W ater Quality

Balancing reserv oir is an intermediate w ater storage tank betw een the w atercourse and the farm. Ev en in high rainfall areas, agriculture is not sustainable in the absence of w ater storage structures. Inflow components i.e. w ater av ailability of canal w ater , groundw ater and rainfall occurrence ov er the balancing reserv oir . The outflow components mainly w ater requirements for crops and ev aporation from surface area of w ater balancing reserv oir , balance the w ater storage capacity that mitigates the w ater demand of the crops and on the basis of balancing components deciding the design of w ater balancing reserv oir . A comparativ e analysis rev eals that the part of this capacity results from a v ery significant dev elopment of balancing reserv oir (particularly in the smaller range of sizes) in the time interv al, probably as a response to rapidly declining canal supplies. The rainfall trend analysis shows that the rainfall occurrence at probability at 50% chance is 370.8 mm which occurs once at tw o y ears of recurrence interv al that shows the occurrence of surface as w ell as subsurface w ater to the study areas. A fundamental implication is that field 'losses' such as seepage and percolation do not necessary to represent losses at a larger scale.