The document proposes a water management system for a hostel block in Jadavpur University, Kolkata. It aims to reduce water wastage and expenses by recycling greywater and harvesting rainwater. Untreated pond water would be used for bathing and washing, while harvested rainwater would be purified using solar energy for drinking throughout the year. The system would make the hostel block independent of underground water sources except in emergencies.

1. WATER MANAGEMENT SYSTEM FOR A HOSTEL BLOCK OF JADAVPUR UNIVERSITY, KOLKATA A PRESENTATION BY : PROBHASH KUMAR BISWAS TIRTHANKAR SARKAR

3. DISCHARGING OF BLACK WATER TO GROUND THROUGH SOAK PIT RECYCLING OF GREY WATER GREY WATR FILTER CUM FLOCCULATOR MAXIMUM WATER LEVEL SEPTICTANK SOAK PIT INFILTRATION GALLERY STORAGE TANK PUMP PUMP SAND LAYER BRICK BALLAST SUPPORTING WALL PORUS CERAMIC PIPE OF Φ 150 MM BRICK VAULT CONTAINING WEEPHOLES TO STORAGE TANK INFILTRATION GALLERY RECHARGE PIT COLLECTING WATER FROM ROAD RUN OFF

4. GREY WATER FROM TOILETS PUMPED TO POND POND HYACINTH TILAPIA INFILTRATION GALLERY STORAGE TANK PUMPED UP TO ROOF-TOP STORAGE TANK USED IN TOILETS FOR BATHING AND WASHING FLUSHING OF WATER CLOSETS DISINFECTANT ADDED

5. RAIN WATER HARVESTING FOR DRINKING PURPOSES Considering the area around Jadavpur :- Annual average rainfall is 1.919 m (say 1.9 m) No. of rainy days are 146. No. of non rainy days are 219. Roof top harvesting potential of the ‘D-Block’ :- Area of terrace is 325 sqm Runoff coefficient for roof is 0.85 (85%) Volume of rainfall on the terrace is ( 325 sqm X 1.9 m X 0.85 ) = 524.9 cum (say 525 cum) By proper harvesting procedure we can harvest at most 70% of the total rainfall. Volume of water that can be harvested = (525 X 0.7) = 367.5 cum Storage potential :- Nos. of boarders in the hostel = 100 (maxim.) Per capita consumption for drinking and cooking = 10 litres. Yearly water requirement for drinking and cooking = (100 X 10 X 365) = 365000 litres = 365 cum of water < 367.5 cum. Hence if we design a rain water storage tank of size 12 m X 10 m X 3.25 m = 390 cum, it would be good enough to store drinking and cooking water for use, throughout the year. # [Provided that the water is properly harvested and purified.] SOLAR WATER PURIFIER SEMI UNDERGROUND WATER STORAGE TANK SOLAR WATER PURIFIER ROOF TOP WATER RESERVOIR

6. OBTAINED FROM RAIN- WATER HARVESTING PRODUCING GREY WATER PRODUCING BLACK WATER OUT OF THE 98 LITRES OF GREY WATER SAY 85 % IS SENT BACK TO THE POND FOR RECYCLE BY EACH PERSON EACH DAY. HENCE ( 0.85 x 98 = ) 83.3 LITRES OF WATER IS RETURNED OUT OF 128 LITRES TAKEN FROM THE POND BY EACH PERSON EACH DAY. SO EACH PERSON DOES NOT RETURN ( 128 – 83.3 = ) 44.7 LITRES OF WATER TO THE POND EACH DAY. SO 100 PERSONS IN 219 DRY DAYS DOES NOT RETURN ( 44.7 x 219 x 100 =) 978930 LITRES OR 978.93 CUM OF WATER TO THE POND WHICH HAS A CAPACITY OF ABOUT 15000 CUM OF WATER. HENCE ONLY ABOUT 6 . 5 % OF WATER IS REDUCED FROM THE POND DURING NON-RAINY DAYS IN A YEAR, WHICH IS NEGLIGIBLE COMPARED TO THE RAIN FALLING ON THE POND IN THE RAINY DAYS. INTAKE FROM POND PURPOSE QUANTITY OF WATER REQD. DRINKING 2.5 LITRE COOKING 4.5 LITRE ABLUTION 18 LITRE WASHING CLOTHES 15 LITRE BATHING 30 LITRE OTHER WASHINGS 35 LITRE FLUSHING OF W.C. 30 LITRE TOTAL 135 LPCD