Peak water losses of evaporation occur between May and June and can be figured as 350 mm/month that is 12 mm/day. Evaporation and seepage losses should be replaced weekly. Two nursery and two rearing ponds should be filled each week. The amount of rain water is neglected in this calculation.
| Filling of ponds: | |
2 × 1 000 m3 + 2 × 5 250 m3 = | 12 500 m3 |
| Losses: | |
12 mm + 20 mm × 7 days × 8.14 ha = | 18 234 m3 |
| Weekly water demand = | 30 734 m3 |
The pumps operate 6 days weekly and 16 hours daily. The required pumping capacity is:
= 320 m3/h = 89 l/s
The recommended pumping capacity:
| 2 units 45 l/s | Total: 90 l/s |
| 1.61 cusec. | 3.22 cusec. |
