Large septic tanks being installed in a dug trench.

Seattle Solution: Buried Water Tanks


Close-up of a worn, metallic fountain pen nib on a black surface.RainBank Rainwater Systems designed and installed a potable rainwater collection system for a remodel in Seattle City limits. The customer wanted to supplement city water usage with “as much storage as possible”, but had very limited space and aesthetics were a main concern. The solution came withtwo 5,000 gallon buried water tanks in the middle of a very small backyard.

Close-up of a worn, metallic fountain pen nib on a black surface.Always appreciatinga challenge, RainBank dug right in with itsawesome excavator, Shane, who managed to export over 120 square yards of soil off site, set the dead men anchors, and nestle the two fiberglass tanks in place with the touch of a feather. The buried tanks were strapped to the dead men (anchoring) and connected together with a 4″ crossover valve. He then backfilled 80% with 5/8″ drain rock while Chad, RainBank’s engineer, took careful deflection readings to be sure the fiberglass tanks were not being distorted during the process.

Close-up of a worn, metallic fountain pen nib on a black surface.Our plumber, Tracy did a great job of use of space on this project. Using 4’x 20′ canisters with sediment, carbon, and 1 micron sediment for cyst removal, followed by a class “A” UV, the filtration train provides potable whole house demand. The system was designed to be easily maintained so the homeowner can be hisown purveyor of clean, safe, reliable water. With the amount of collection area, annual rainfall and frequency, this two person occupancy should be able to meet 100% of itshousehold use, but also have city water as a backup, just in case.

Many thanks to our customer for sending us this email note. A big thank you to you for giving us our water system. We are enjoying our “free” water immensely.”

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.