Question

The following Table gives monthly flows, precipitation, evaporation and demand rates for a critical 12- month period at a proposed reservoir site. Existing water rights require a monthly release of 10000 m'. The average reservoir area is 4 km-. Compute the required reservoir capacity. Mo Natural Monthly Monthly Monthly Water mean Pptn Evapn Demand Rights flow Release (10 m) (mm) (mm) (10m) (10 m) '1 3.37 130 50 0.75 0.1 2 3.03 53 83 1.05 0.1 3 3.71 45 88 1.35 0.1 4 1.47 30 105 2.10 0.1 5 0.52 13 153 0.1 6 0.25 5 205 2.63 0.1 0.60 3 260 2.58 0.1 8 1.25 0 278 2.30 0.1 9 3.75 28 180 1.14 0.1 10 4.00 80 128 0.91 0.1 11 4.20 113 80 0.82 0.1 12 4.30 145 13 0.65 0.1 2.42 7

Answer 1

for 1st month 2 As - (8.37 -0.75-0.120+ (O.13 -0.05)X 4000 X HOVO X 106 20602de 6 + GROMO z (2652 2 2084X106 m3 +0.32) x 100 m3 For 2nd month 8 A5= (3.05-1.05 – 0.1 Alof (0.053-0.083)x4X106 2(1088) x 106 - 0.12 x 106 1.76x106 m² for 3 rd month AS₃² 2 BODO (3.71–1:35 -0.19X108 + (0.045-0.083) XAX z (2.26 - 00172)x106 = 2.088 x 10m3 for 4th month Asus (1•47 - 2010 - 0.1)x106+ (0.03 -0.105) X4 X106 2 -0.877x106 0.3x106 2 -10177 x106m3

For 5th month Assz (0.57 -2.4-0.1) X106 + (0.013-0453) X4X106 =(1.95-0.56 ) x106 2 -2.51 Room² for 6th Month AS - (0.25 -2.63-0-1) X106 + (0.005 - 0.205)x10x4 242.48) x 106 10.8 x106) 2 -3.28x 106 m² for 7th Month As, 80.60 –2058-001) + (0.003 - 01260) xif x100 2- 3. 108 x 106m3 For 8th Month AS ² { (1.25=2.30-0-1) + (0-0.278) x 43 x 106 2 -2.262 x06m3 for gth month 4892{(3.75-614-0-1) + LOO28 -0.180)x 4}x106 (2.51 -0.608)*106 z 1.902x 106m3

for 10th Month AS 3 (4.00 -0.91 -0.1) 8106 f (0.08 -0.128) x4 x106 220798x10 m² for uth month AS,= (4.20 -0.82-0-1) x 106 + Co.113 - 008) x 4 X106 = 3412 x 106m² For 12th month AS, 2{(430 - 0.65-00) + (0-145-0.013) x4} x 106 4.078 x 106 m² Z .. Net Change in storage a 6.541x106m3 Resovo Regosired AS FAX2+1SATASg tasb c & Kray z 18.878 Capacity of Reservoer = Max. & Asn} 24.078*106 m3