RAIN CAPTURE or RAIN HARVESTING is becoming increasingly popular for landscape irrigation due in part to recent improvements in drip irrigation technology.  A one inch rain on a 2000 square foot roof generates over 1000 gallons of free water. Arid western states such as New Mexico and Arizona support and promote "Rain Harvesting" which returns moisture to the soil at slow absorbable rates, with very little evaporative loss, when applied through a subsurface irrigation system.

Always make provision in your collection system for a high volume bypass to divert excess rain water that can not be filtered and stored fast enough. Also consider a tank overflow to release any excess water when the storage system is completely full. Both the bypass and overflow must be directed away from the tank and discharged where it will not cause erosion or structural building damage.

We do not recommend that you drink or bathe in rainwater unless it has been treated to your local Health Department standards. Rainwater should rightfully be used in a way that returns the moisture to the earth near the location where it fell, such as through outside landscape irrigation or a septic system leach field.

Roof water generally carries leaves, dust, bugs, bird excrement, and a variety of other undesirable elements into any rain capture storage system. Filtering the water before it fills the storage system is desirable provided the filter has the capacity to process the rain as fast as it falls. This may be difficult to do in the case of a "cloud burst" event.

The following illustration depicts our modular OcTank system with a simple filtration and clarifier module, upstream bypass, strainer basket, and high capacity washable fabric filter.

Any clarifier or sludge tank will require some maintenance. The strainer basket and washable filter must be cleaned regularly and accumulated silt in the bottom of the clarifier module may need to be "mucked out" every couple of years by hand or vacuum truck.

Darco Underground Water Storage Tank Applications
potable water | fire cisterns | rain capture | wastewater treatment | gray water
agricultural | landscape/water features | storm water detention | fire sprinkler reservoirs