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.

Seattle Households Benefit From Rainwater Collection Year-Round

seattle-skylineWith an average annual rainfall amount of 37.5″, the Seattle area is an ideal environment for rainwater collection, since Seattle area households see a moderate climate compared to other cities in the United States.  Summers are generally short and winters are fairly moderate.

Let’s take a look at an average 2,500 sq. ft. home in Seattle, which can easily sustain itself while using rainwater collection for whole household use.

Autumn rainfall averages around 11.55″, filling tanks from the past summer’s use quickly with 17,911 gallons of water available for collection. Winter averages are around 14.42″ or the equivalent of 22,459 gallons available to keep tanks full. Spring continues with 13,036 gallons from an average of 8.37″, allowing levels to remain high. Even summer at an average of 3.15″ or 4.906 gallons available should keep tank levels from going dry to be filled again in the fall.

Seattle Precip 2015Depending on use, an average Seattle home can sustain itself on harvested rainwater without any change in lifestyle for the residents. The average demand from one occupant is 35 gallons per day or 1,050 per month – not including irrigation. Being connected to city water allows for a back up supply. Even with a small amount of storage, a supplemental system can conserve city water supplies and save money, by providing full usage during the wet periods. Future weather patterns predict wetter warmer winters and hotter, dryer summers. A look a last year’s averages on the above graph suggests this to be true. Rainwater collection is a perfect fit for Seattle residents whether non-potable or potable use is desired.

Underground Rainwater Storage

Green Tank ExcavationMore urban customers are inquiring about underground storage for rainwater catchment systems. With limited space in a typical city backyard and the desire to keep what little space there is unobstructed by large cisterns, buried tanks are the solution.

underground tankThe decision to choose underground storage comes with added costs.

Below grade cisterns require considerations and costs that are not typical with above ground storage. Structural requirements, added excavation, and drainage are factors in costs. The costs of engineering and materials add to the manufacturing costs of below grade cisterns. Added labor, such as excavation, more than likely will include the need to export soil off the site and the import of drain rock. Buried tanks require cement hold-downs and proper drainage of tank placement to eliminate possible floatation of the tank when water levels in the tank are low and ground water levels are high. Below grade cisterns can be 2 to 2.5 times more expensive than above ground to design, purchase and install properly.

Buried tanksExperience in below grade cistern design and installation is the key factor in the success and costs of the project. Understanding the added costs before hand will help ease sticker shock.

 

Can You Disconnect from a Municipal Water Supply?

drinking water from fountainWhile you cannot disconnect from most municipal water supplies in Washington State, you can include a non-potable rainwater collection system as a supplementary source statewide.

Since October 2009 Washington State legislature has accepted rainwater collection for non-potable use for residential and commercial application. Irrigation, toilet flushing, laundry facility and wash down are all acceptable usage of rainwater.

King, Jefferson, Island, San Juan, Skagit, and Whatcom counties have all adopted potable use of rainwater for a single-family residence as supplemental. Most allow for sole source or off grid use if there is a “hardship” involved with a well or community water source. Some cities within these counties do not allow potable use therefore it is recommended that homeowners who are considering rainwater harvesting should check with their county and city health departments for regulations and requirements.

RainBank’s President Ken Blair actively works with counties and cities to promote the practice of rainwater collection for potable use. With aging infrastructure, increasing demand, and water quality concerns, rainwater collection is being recognized as a viable source of drinking water.

Depending on your roof size, annual rainfall, and demand, you can supplement up to 100% of your household use. An average 2,000 square foot home with 36″ annual rainfall will yield over 44,000 gallons annually. Whether you are building a new home or own an existing home, urban or rural, rainwater catchment can provide a safe, reliable source of water, with quality of water exceeding most well and public water sources. A properly designed and constructed system with quality filtration and ultraviolet disinfection is easily maintained by the homeowner, allowing the homeowner to be in charge of their household water.

RainBank Rainwater Systems has been designing and installing potable rainwater catchment systems for 15 years and President Ken Blair is an American Rainwater Catchment Systems Association (ARCSA) accredited professional, Inspector Specialist, ARCSA Northwest Regional Representative, and lifetime ARCSA member.