Monthly Archives: April 2016

Environment, Rainwater Catchment

Can Seattle Area Residents Opt Out of City Water?

gift-505591_640Saving money and helping the environment are two good reasons why many Seattle residents choose to opt out of city water usage. Whether the application is for potable (drinking) or non potable use, like irrigation, supplementary tanks with even a small amount of storage can help drop water bills by as much as 80%.

Collect 624 gallons of water from 1 inch of rain with only 1,000 sq ft of roof area.

That’s water that you can use for irrigation, toilet flushing, laundry, or even whole house potable (drinking) use. That’s right! 624 gallons. If you have a 1,500 square foot roof area in the Seattle area, this equates to 33,642 gallons of available water. Water that you don’t need to pay for. You can save money on your water, and sewage bill and, over time, pay for your system with that savings. Depending on the application of the captured rainwater, you can supplement your usage through a simple collection system for irrigation or by plumbing in your toilets and laundry facilities. Or, if you choose to have a whole house system designed and installed by a professional, you can eliminate your municipal water usage altogether and have city water as only a back up supply.

Water quality of collected rainwater after filtration and UV disinfection is above that of a municipal water supply, as long as the system is designed, installed and maintained properly. Annual costs of maintenance is much less than your current water bill and is easy to do. Periodic cleaning of your gutters and screening devices along with filter changes a few times a year and replacement of the UV bulb once a year is all there is to it.

A decentralized private water system eliminates the possible threats to your drinking water from environmental concerns, water advisories, price increases, additives such as chlorine and fluorides and possible rationing, such as in California. You are in control of the quality of your water and its use.

Not a new concept, in the past few years, rainwater collection has become wildly popular as a safe source of water for households and businesses in Washington State. As with any industry, know your pro. An ARCSA accredited professional and ARCSA’s NW Regional Representative, RainBank’s Ken Blair has been designing and installing systems for 15 years. The team at RainBank is bolstered by an on staff engineer and plumber. When planning your system, consider RainBank Rainwater Systems to be your one-stop choice for design, water tank and component sales, installation and consultation.

This article was originally published under the title Rainwater Harvesting Lets Seattle Area Residents Opt Out of City Water at RainBank.info

Rainwater Catchment, Residential Rainwater Collection

Seattle Solution: Buried Water Tanks

Buried water storage tanks 3RainBank 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 with two 5,000 gallon buried water tanks in the middle of a very small backyard.

Buried tanksAlways appreciating a challenge, RainBank dug right in with its awesome 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.

20150720_145650-2Our 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 his own 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 its household 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.”

Rainwater Catchment

Consider Future Demands on Rainwater Collection System

rain-gauge-907678_640When you calculate area rainfall – measured annually, monthly and daily, plus factor in how the water will be used in the future, you can determine how much is storage is necessary to meet your needs.

Being aware of current water use is helpful with knowing how to size a system, but don’t neglect to consider potential future demands. If you’re planning a family, entertaining, have a growing business, or may sell the dwelling and property, you want to account for those scenarios when you calculate storage. At best, the system should be professionally designed and built to meet future demands as well. Here are more reasons to consider future demands when building a rainwater collection system:

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.

When you know how you currently and potentially will consume collected rainwater, plus install water efficient fixtures and by employing best conservation practices, you will have enough during periods of high demand or drought, when you might have to cut back or switch to an alternate source. If you plan for this during the design process, you will have a system that works for you far into the future.

This article was originally published under the title Estimating Water Usage for a Rainwater Collection System at RainBank.info