In 1984 we built our first concrete water tank.   
                    Design parameters were:

1) Build tanks that would out last any other
2) Use as little petroleum based products as possible
3) Create as little waste of materials in construction

Water aqueducts built by the Romans using concrete are still in use today.  Our design makes use of rebar modules in such a manner that, of the close to two tons used in the 20,000 gallon tank, approximately 30lbs end up as cut off waste.  These become part of other projects or are recycled.

Our forms are built of steel and plywood and have been reused many times.  The finished product is sealed with a mineral based material approved for potable water.  Whether above ground or partially buried, visual impact can be minimized.

Because of the longevity and lasting value, clean storage of water without the use of plastic or galvanized metal and the low visual impact, we feel our design was "green" long before the term became popular.