Howdy. I will build a barn (rainwater harvesting) on a ridge about 100 ft in elevation above my house. I currently use 2 1500 gal poly tanks to catch rainwater from the house roof ... they are a royal pain in the butt to clean out! I would appreciate thoughts about cistern options on the ridge. A concrete truck can not get up the ridge. This will supply drinking water, treated at the house. I will need about 10,000 gal. to meet garden irrigation, household, and fire protection needs. We get 58 inches of rain a year with the lowest month being about 3.5 inches .... you could almost say we get 5 inches a month. I have considered:

1) The poly tanks ... but my wife and I are not "young" any longer and I would rather have something easier to clean.

2) A concrete block tank but the floor would have to be poured by hand, piece meal. What are my options to seal the block and the floor ... a liner? ... fiberglass? ... some "plaster?" ... bituminous material? I'm pretty uneducated about these issues.

3) An above ground swimming pool with cover?

4) ?

I would greatly appreciate all information/thoughts etc., especially links to other sites with information/products. Thanks in advance.