I designed this cistern myself. Feel free to copy the design. It works as designed.
Weight Considerations:
When full, these barrels weigh a bit over 200kg (440 lbs), so 10 of them will weigh about 2000 kg (4400 lbs). The cinderblock base is not mortared together .. it's just stacked in place. Weight of the base is about 3400 kg (7500 lbs) and rests on sandy soil. The base sat for about 6 months before I started loading the barrels with water so I could see whether it would settle. It was perfectly flat when I laid it, and when I installed the barrels, the outermost blocks had settled about 5 mm (3/16") which required a small shim under the base plates on the outer edge.
Costs:
Barrels: $150
PVC: $160 (est - All the 4" PVC was free from Craigslist)
Plywood (5/8 exterior): $30
Cinderblocks: $Free (Thanks, Craigslist)
Total: ~$350
Water cost: $6/100 c.f.
Storage: 66 c.f.
Estimated use: 3 turns per summer = $20
Estimated return on investment: 18 years (at current rates).
Note: If I had to pay retail for the cinderblocks at $1.45 each, the cost of the cinderblocks alone would have approached $300 and made the project not cost effective.
Water collection calculation:
Roof Area: ~330 square feet.
Gallons collected per inch of rainfall: 200
Rainfall required to fill the barrels: 2.5 inches
14 окт 2024
