What is Seattle’s Position on Rainwater Collection?

Underground Tank Construction3In October 2009 Washington State revised its water rights laws to allow rainwater collection. King County (Seattle) has adopted rainwater collection for potable use in single-family dwellings, as well.

Seattle and King County encourage the practice of rainwater collection. King County Health Department / Plumbing Division reviews designs, approves designs for permitting, and inspects installations of RWC for potable and non-potable use. Only an engineer, licensed in the State of WA with experience in RWC or an American Rainwater Catchment Systems Association (ARCSA) accredited professional can design systems for potable usage. Currently potable use is only allowed for single-family residences, not public. Non-potable use, such as toilet facilities, wash down, irrigation, and laundry is allowed for public use.

A simple irrigation system not connected to household water usually does not require a permit. If a rainwater collection system is connected to household plumbing a “reverse pressure back-flow assembly” (RPBA) is required to be installed on the city water line entering the dwelling or building and requires a yearly inspection by a licensed plumber that carries a current endorsement. The RBPA can be waived if an “air gap” is installed so there is no cross connection between city water and the collected rainwater.

There is current code for rainwater collection that must be met for permitting and installation. Green Stormwater Infrastructure (GSI) was enacted to control stormwater runoff and mandates that all new construction, commercial and residential have a stormwater management plan in their design. Infiltration or use of runoff is mandated by City of Seattle, King County and State.

Seattle Public Utilities has initiated a rebate program called Rainwise a few years ago, which encourages infiltration on site and is seeing some success in stormwater with small residential rain gardens. Governor Inslee has requested a small amount of money for education on conservation from the emergency drought relief fund.

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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.

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