Quality of Harvested Rainwater

Whether your rainwater harvesting system is for non-potable or potable use, there are key factors that dictate the quality of that collected water and the success of your system.  Collection surfaces should be compatible with intended usage.  While an asphalt shingle roof may lend itself for collection of a non-potable demand, a baked enamel, metal roof would be preferred for potable use.

Rainwater that has been collected in a manner that reduces debris and contamination will store better than that which has not. Bacterial growth can be kept to a minimum by prescreening and aerating rainwater entering storage. Diffusing, or calming water entering storage will reduce disturbance of any sediment, allowing microorganisms to do their job by eating bacteria. All inlets and outlets of cistern(s) should be screened and protected from insects and vermin entering the storage tank.  Mid-level in the water column is the cleanest source of water to be delivered to the pressure pump and can be achieved with a floating/screened suction.

Properly designed and installed conveyance and storage should require little maintenance, but should be looked after by the purveyor. Gutter system and screens should be inspected and cleaned as needed, especially during pollen season. Debris in the gutter should not be allowed to enter the conveyance lines. Periodic inspections will reduce the buildup of unwanted debris that may cause odor or discoloration of your stored water.

By conveying and storing your harvested rainwater properly, your pressurizing and filtration system will operate to its greatest potential, producing quality domestic water for both non-potable and potable demands.

Ken Blair
A rainwater collection systems designer and consultant, Ken has designed and installed residential and commercial systems, primarily in the northwest United States for more than 10 years and, in 2014, began consulting and managing builds in other states. Ken is an accredited ARCSA Professional Designer / Installer and Life Member, the Northwest Regional ARCSA representative and advisor to its education committee and is available to speak about Rainwater Collection Systems design and builds.

Ken is a United States Navy veteran, having served on active duty during the Vietnam War era.

A career entrepreneur, Ken created a new business focus with a commercial dive company in Hawaii in the mid 1980′s to respond to and clean up oil spills, oil spill equipment training, service and maintenance for the oil co-op service industry. Ken is passionate about having a positive impact on the environment and is also a founding director of BANK-ON-RAIN (2011-2014), whose mission is to create grassroots solutions for rainwater collection for consumption and agriculture in developing areas of the planet.