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.
Infrastructure, Rainwater Catchment

Rain Harvesting in National Spotlight

waterfall-329155_1280The American Rainwater Catchment Systems Association, ARCSA, is a driving force in placing rain harvesting in the national spotlight by petitioning President Obama’s administration to focus on the broad economic value of supporting and encouraging growth in the rainwater harvesting industry.

According to ARCSA’s petition, rain harvesting is not just a sustainable source of water, the rainwater harvesting  industry is building infrastructure “creating new jobs in design, installation, education, R&D, sales, plumbing, landscaping, roofing, monitoring and maintenance, which could propel the U.S. to international leadership, with compounding fiscal benefits.”

The petition has been submitted and is seeking 100,000 signatures in order to qualify for an official response.  Please click here to read more and to sign the petition.

Rainwater Catchment

Drought Emergency Declared in Washington State

drought washington stateWhile rainfall amounts in Washington State are at 100%, it is the snowpack that has Governor Inslee expanding drought declarations.

Urban water supplies expect to be unaffected; the reservoirs are about where we want them to be. “The snow pack above Coulee Dam is running above normal”, according to Michael Hansen, Bonneville Power Administration. Hansen goes on to say, “We’re not anticipating that we’re going to have any problem meeting our obligations”.

20150414_wa_noneSnow pack in the Cascades is 7-50% of normal and the Olympics at only 7% at the end of March. The US Drought Monitor shows that the affected areas of “abnormally dry” is the North Eastern part of the state with the South Eastern being “moderately dry” while the Olympics are at “moderately dry”.

The reduced snow pack and its limited runoff, will have a negative effect on in stream flow rates in most of our rivers this summer. Joe Stohr, Department of Fish and Wildlife, commented that “Drought could also reduce streamflows that make it harder for fish to migrate.” It is expected that rural areas will see more of the effects than urban areas such as Seattle, Tacoma, etc. But, this could change, as we get further into the normally drier months.

Most of us aren’t even aware that the last statewide drought declaration was in 2005, because of large reservoirs and reserves. We’re fortunate for our climate and our mountains to make drought conditions short lived. With a little conservation and emergency procedures for irrigation of our farmlands, little effects on our lives will be experienced. Reduction of demand on wells will help our in stream flow rates, and temporary closures or limits on fishing will help our salmon. Conservation now rather than waiting to see what happens is good policy. While it is unlikely we will ever see drought like California is experiencing, we should practice measures to ensure our natural habitat and protect it for future generations in Washington State. Simple conservation techniques will support a healthy environment and balance of our eco system.

Rainwater Harvesting Education

Estimating Water Usage for a Rainwater Collection System

Rainwater Collection TanksIn order to establish usage for a rainwater collection system annual, monthly, and daily rainfall amounts,  along with water usage demands need to be taken into consideration.

Current water use is informative to help with sizing a system, but future demands should be considered as well. Growing family, guests, possible resale of the house should be accounted for. The system should be designed and built with upgrades for the future in mind, allowing for the system to supply what the future may hold.

Possible drought or longer periods of dry season should also be considered when designing or building a system. Incorporating back up water supplies into a system can be as easy as hauled water, or drawing from a well, community or city water system and should be an available option for those times. Residential rainwater systems in the city are often limited in space for storage, leaving the volume of the cisterns inadequate for year round use. Having the ability to switch to this alternate source can be a necessity in design. However, a more rural environment lends itself to larger storage capacities.

Water demand is an important part of design and the American Water Works Association (AWWA) has conducted a study of various fixtures and appliances. Knowing these demands will help estimate usage and assist the designer to adapt the design accordingly. Single flush toilets use 1.28 gal/ flush, dual flush toilets 1.0 gal/ flush for liquids and 1.28 gal/ flush for solid. Average use is 6 flushes per person, per day. Low use fixtures such as shower heads, faucets, cloths washer (front loading) are recommended for the overall design of the house and can be found in publications from manufacturers. 

Outdoor demand should be limited as much as possible. Drought tolerant plantings, drip irrigation, and general conservation will  help limit outdoor usage.

For specific irrigation needs, Evapotranspiration (ET) is the measurement of amount of water in inches that is needed to grow plants. All plants have a different watering requirements, also being affected by temperature, wind, humidity, and sunlight. A state climatologist can be contacted to attain an ET standard reference for your area. Careful consideration of outdoor use must be given if irrigation is part of the RWC design. An average city lot can use as much as 1,800 gallons of water for watering a lawn.

In order to get the best performance from your rainwater collection system, indoor and outdoor demands must be carefully calculated using best storage capacities, surplus and defect, level of storage, daily, monthly, and annual  use/demand for the entire year. Simply calculating the average annual rainfall amounts will not produce the end goal of a well designed RWC system. It is best to determine average potential of collection and use. Determine average daily, monthly, and annual rainfall amounts. Calculate collection area, and determine runoff. Identify highs and lows of rainfall amounts and demands. Determine those months of low amounts of rainfall along with the carryovers from months prior. Certainly, identify those months of zero rainfall.

Know your consumption of current and future use. Use water efficient fixtures and practice conservation. Understand that during those times of low amounts of rainfall, you may need to “tighten the belt a bit” or switch to the alternate source. Determine your desires and demands during the planning stage by doing so your system will produce the results you are looking for.