Cement, Energy and Environment

Table No.6: Ground water level of the tube wells in study area after implementation of rainwater harvesting TW2 23.81 25.81 13.42 7.81 3.51 1.64 3.96 5.02 7.03 8.07 12.42 14.81 TW3 25.21 26.84 15.64 8.21 4.54 1.46 3.86 5.24 7.46 9.01 11.50 14.27 TW4 24.64 26.84 16.01 8.44 4.50 1.84 3.41 5.04 8.81 8.81 12.11 15.09 TW5 25.61 27.51 16.23 8.32 4.81 1.86 3.91 5.35 8.89 8.89 11.50 14.08 TW6 23.64 25.24 15.29 8.01 5.04 1.94 3.88 5.21 8.73 8.73 11.47 13.67 TW7 23.41 26.41 18.24 9.21 4.71 1.47 3.01 5.1 8.66 8.66 11.50 13.81 TW8 23.21 26.01 17.92 10.69 4.81 1.98 3.56 5.21 7.6 7.6 10.68 12.25 TW9 26.24 29.47 24.54 14.42 4.88 3.34 4.17 6.92 8.21 8.21 13.47 15.09 TW 10 34.42 36.14 27.24 15.33 6.81 3.34 5.08 7.86 8.71 8.71 1 13.28 16.21 TW 11 32.24 35.24 28.24 15.81 7.30 3.95 5.38 8.02 9. 12 9.12 13.24 16.60 General rain water harvested can provide the supply of potable water, in addition to non potable usage i.e., toilet flushing, vehicle washing , floor washing and agriculture but in the present study the Furaat rain water harvesting system has provided few additional advantages which result in good quality filtered water, free of suspended solids for domestic use. In the present situation rain water from roof top is collected through pipes and convey into first well in this well as the water flows horizontally through a horizontal filter were in dual process of both sedimentation and filtration is achieved. In this filter first half is filled with gravels were larger suspended solids get trapped between the spaces between the gravel bed. Remaining water when passes through the second chamber sedimentation occurs and the suspended solids settles at the bottom. Supernatant goes to the second step well containing sand which act as sand filter. Second chamber of second step well is provided with non clogging stainless steel screen preventing floating debris. Treated and filtered water from the second step well is directly conveyed to the aquifer through the tube well. This rain water harvesting not only collects the rain water but also provides good quality treated water. To authenticate the efficiency of this rain water harvesting system the water from the wells were analysed for routine important parameter. pH of the tube well water before and after rain water harvesting did not shows much variation. It varied between 7.43 and 8.62 and 7.36 and 8.46 before and after rain water harvesting respectively clearly indicating that there are no such rocks which imparts the water acidic or alkaline. Fluoride concentration also remains more or less constant with very marginal or insignificant reduction after rain water harvesting. Fluoride concentration has not increased indicating that there is no fluoride bearing rocks in this area. Total dissolve solids, total hardness and chloride have shown decreasing trend after rain water harvesting. Where ever conventional recharging was followed the quality of water did not indicate any improvement in the quality compared to Furaat System. All the routine parameters were on the higher side before implementing rain water harvesting system this is due to the dissolution of calcium magnesium and lime during water percolation through soil layer. While during the implementation of rain water harvesting system by Furaat, collected rain water goes through a series of primary treatment and then the treated water is conveyed directly in to the aquifers, thus eliminating the dissolution of calcium magnesium and chloride through soil layer. Combination of a good average rain fall and required roof tops makes the situation ideal for conservation of roof-top rain water in Durg area during monsoon to augment groundwater storage 6