All posts by 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.
Rainwater Catchment

At What Point is Rainwater Collection Too Expensive?

water-49024_640Collecting rainwater for potable and non-potable use should carry the importance of what it is “a safe, reliable source of drinking water” that protects the health and welfare of its users. What is that worth? At what point do we consider rainwater collection to be too expensive? Only hire those that are qualified, not those who are the cheapest.

As rainwater collection becomes an increasingly accepted, sustainable method of water conservation, costs have risen due to design and implementation regulations, as well as major components improvements. As in any industry, qualifications of designers and installers are, and should be scrutinized.

Liabilities need to be addressed for potable and non-potable use, not just for the designer or installer, but for the owner of the system as well.

For non-potable application, care must be given that fixtures, as well as plumbing, are clearly identified as “non-potable water unsafe to drink” and plumbed in such a way that cross contamination to potable water does not occur.  A reduced pressure backflow assemblies (RPBA) or air gap must be installed on city water side of plumbing if non-potable water is connected to any building or dwelling plumbing system. This protects the safety and welfare of users and their guests. A qualified designer/ installer must remain current with plumbing codes that are in effect for rainwater collection.

For potable application, great care must be given to design and installation, after all we’re talking about drinking water and the safety of the user and their guests. EPA standards of quality of drinking water must be met, or the designer, installer, and homeowner can be liable. The American Water Works Association (WWAA), the American Society of Plumbing Engineers (ASPE) along with the American Rainwater Catchment Systems Association (ARCSA) have written plumbing code for RWC which are continuously being updated. The designer needs to know what he or she is trying to remove from the raw water and use the best method of filtration and disinfection to protect the safety and welfare of others. All components including storage, conveyance, filtering, and disinfection must meet National Sanitation Foundation (NSF) requirements for drinking water.

Many counties in Washington State, including King County, require a licensed engineer, with experience in rainwater systems, or an individual who holds a class B water designer certificate or an ARCSA AP. Professionals that are installing pressurized systems are required to have a plumber’s license. This regulation helps protect the health and welfare of the system owner. ARCSA APs must submit continuing education credits to stay current with their endorsement.

We’ll let you decide when RWC is too expensive, but encourage you to consider the value of having your system installed safely and to meet city, county, state and federal mandates.

Rainwater Catchment, Residential Rainwater Collection

When is Permitting Required for a Seattle Rainwater System?

When is permitting required for a rainwater collection system in Seattle?

wave-499476_640According to Department of Ecology, State of Washington, collecting rainwater is nothing new. Humans have been doing so for thousands of years. Washington State Department of Ecology began allowing rainwater collection without a water rights permit in October 2009.

In January 2011, King County Department of Health adopted rainwater collection for potable use for detached single-family dwellings. The policy applies to systems intended to capture and store rainwater from surfaces for supply to plumbing fixtures. Systems that supply untreated rainwater to serve non-potable fixtures may be used for both residential and nonresidential occupancies. Systems that treat rainwater for potable use may be used only in detached single-family dwellings.

Rainwater systems are subject to plan review and applicable fees by the Department of Health and the Building Department. Harvested rainwater that is not treated to potable standards may only be used for water closets, urinals, hose bibs, industrial applications, domestic clothes washing, irrigation and water features.

Rainwater collection systems require a water use permit by King County Department of Heath. A non-pressurized stand-alone irrigation system does not require permitting. All pressurized systems do require review and permitting by King County Heath.

Systems for residential, potable use must be designed by a licensed engineer with experience in water systems design, an individual with a group B water systems designer licensed by King County Health, or an American Rainwater Catchment Systems Association (ARCSA) accreditation.

Rainwater Catchment, Technical Information

Considerations for Water Treatment

FiltrationRainBank Rainwater Systems designs and installs custom treatment systems to meet customers’ specific needs.

Harmful bacteria, pathogens, and cysts removal is a must in a potable rainwater collection disinfection train. This is typically achieved with a class “A” UV light. Flow rates are calculated to achieve the correct amount of contact time with the UV spectrum for proper disinfection. The correct class of UV for a specific application is required. A class “A” UV must be used for water that is not deemed safe to drink. A class “B” is only used for water that has already been safe to drink.

But there are other considerations for water treatment. The raw water must be relatively free of sediments, turbidity, organics and inorganics before entering the UV chamber. The UV spectrum will not be able to penetrate the water column effectively otherwise. Special consideration of environmental constituents should also be addressed for proper treatment.

Environmental concerns can include location of collection area. Where is the house located?  Possible hydrocarbons Skagit_Filtrationfrom a nearby freeway would be a concern. Pesticide use from farming or city landscaping maintenance should be considered. Roof material and manufacturing process could pose a health threat and should be addressed – all of which can be corrected with proper filtration, whether it is accomplished with canister elements or back flush devices.

Rainwater is typically acidic, approximately 5.5 to 6.0 ph; nominal being 7.0 ph. The lower ph levels, while not considered harmful to humans, can have a negative effect on plumbing and fixtures. A more nominal ph level can be achieved with proper treatment.

Rainwater is relatively clean to begin with; much more than surface water. It is what it comes in contact with that can change its purity. Proper design and installation of a filtration and disinfection only comes from using the “right tools for the job”.