Tag Archives: rainfall

Rainwater Catchment

How to Save Money with Seattle Area Rainfall

needle-rainWhat could you have done with last weekend’s Seattle area rainfall of around 2.5″?

If your house has 2,000 sq. ft. of roof, you could have collected about 3,000 gallons of water. That could flush toilets for a four person household for 100 days or do over 100 loads of laundry. You could supply both demands in this household for a entire year with as little as 4,000 gallons of storage with our average annual rainfall. The average demand for both of these fixtures is 48% of your household usage. That’s 48% of your water not needed to be distributed through a centralized water system. That’s 48% of you water bill, which is expected to increase consistent with demands, repairs of infrastructure, and availability. 

Rainwater collection can be part of your requirements of the new 2016 stormwater code. Our modal above mitigates over 65% of its roof runoff. With larger storage and other use, as much as 100% mitigation can be met. On site infiltration or rain gardens can also augment the drainage plan along with rainwater collection.

RainBank Rainwater Systems is a full service Design / Build, Rainwater Collection Contractor with more than 15 years in the industry.  We are an American Rainwater Catchment Systems Association (ARCSA) lifetime member and are ARCSA  Accredited Professionals. We offer sustainable, scaled deigns, realistic solutions, and quality construction, using only the best suited and tested components on the market. We work closely with our customers and their architects, engineers, and general contractors to achieve the desired end results. Our team has an in house engineer and licensed plumber in order to keep things simple during design and construction, we also take care of the permitting for you. 

Contact RainBank Rainwater Systems, we would be pleased to talk with you about your project.

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

Environment, Sustainability

Will Museum Become the Place Future Generations Can Experience Rainfall?

They took all the trees
And put them in a tree museum
Then they charged the people
A dollar and a half just to see ’em
Don’t it always seem to go,
That you don’t know what you’ve got
‘Til it’s gone
They paved paradise
And put up a parking lot
Big Yellow Taxi, Joni Mitchell

lock-143616_640Released in 1970, artist Joni Mitchell hit the nail on the head with this lyric from her song, Big Yellow Taxi, practically predicting the future. A recent NY Times article titled Drought Adds Wrinkle to ‘Rain Room’ Exhibit in California, reports on “Rain Room” an exhibit at the Los Angeles County Museum of Art, which gives visitors the experience of walking through rain without getting wet. Motion sensor cameras pause the water as people walk beneath them, “creating a Moses-parting-the-seas kind of spectacle — the exhibit here is truly novel and timely, a reminder of what is missing in the parched West these days”.

One drought-weary Californian commented on the irony, “The only rain we get is indoors, and it doesn’t hit us, said Ken Bruce, who spread his arms wide as he walked under the high-tech rain ceiling in a mostly fruitless attempt to do what people normally avoid at all costs: get wet. I wouldn’t have minded being hit by some of it”.

Museums typically showcase precious artifacts – often priceless items of historical, scientific, artistic value. Has rain become such a precious commodity that  future generations will only be able to experience it in a museum?