Make sure that your water-storage tank (also known as a cistern) has an overflow pipe, a vent, lockable access, and a couple of filters installed at appropriate points in the system. You may also want an automatic recharge line to provide water when the cistern might otherwise be empty. Cisterns are usually installed to collect roof runoff, but in some cases runoff from patios, parking lots, and other impervious surfaces can be collected, conveyed, stored, filtered, and redistributed. Some activewater harvesting systems are designed for drinking, while others are best suited for irrigation, fire prevention, clothes washing, or toilet flushing.
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