Tag Archives: toilet

Rainwater Catchment

Rainwater Saves Money in Seattle

statue-5998_640According to a press release issued by Drexel’s College of Engineering, “research by a team of Drexel University environmental engineers indicates that it rains enough in Philadelphia, New York, Seattle and Chicago that if homeowners had a way to collect and store the rain falling on their roofs, they could flush their toilets often without having to use a drop of municipal water.”

Franco Montalto, P.E., PhD, an associate professor in Drexel’s College of Engineering, and director of its Sustainable Water Resource Engineering Lab states, “Philadelphia and Seattle are the two cities where percent water savings would be greatest if residential neighborhoods were all equipped with rainwater harvesting systems.”

RainBank Rainwater Systems has been designing and constructing systems throughout the Pacific Northwest for more than 15 years. Many of our Seattle customers have included rainwater collection as part of new residential construction and retrofitted existing homes. Toilet flushing, laundry facility, and irrigation can all be supplied with non potable rainwater. Whole house usage or potable water can be achieved with proper filtration and disinfection as well.

You don’t need a lot of storage to save money. RainBank Rainwater Systems has designed and installed 3,000 gallon systems that supply an average 2,000 sq. ft. home with 60% of its household use, simply because of the amount of fall and winter rainfall.

Read more from Drexel University Engineering: Here’s Why We Should Use Rainwater to Flush Toilets

Environment, Rainwater Catchment

Rainwater Harvesting Systems For Irrigation

In my blog posts I often neglect to discuss rainwater collection for irrigation demands, even though the most common use of rainwater collection is for non potable use.

While my focus is often on potable whole house usage for residential systems and irrigation as a means of infiltration for commercial applications, the benefits of rainwater collection for both potable and non-potable demand have positive effects for both applications.

Irrigation demands for both commercial and residential can effectively be supplied by collected rainwater. All new construction in Washington State is required to infiltrate runoff on site. This mandate is intended to reduce runoff that increases urban flooding and pollution. Impervious surfaces, such as roads and parking lots, typically have oils, greases, and heavy metals. Yards often contain fertilizers, chemicals, and animal waste – all of which can be carried off to our streams, rivers, and lakes. Some of these are a source of drinking water in Seattle and other cities. Groundwater recharge is reduced as urban populations grow. Land development dramatically affects groundwater recharge with increased impervious surfaces. A rainwater harvesting system allows more opportunity to infiltrate the soil and recharge groundwater supplies.

roof gutter rainBy capturing roof runoff and storing it for use in irrigation, a developer can infiltrate this runoff on site and meet the requirements set forth by the city and state. Stormwater runoff is decreased; infiltration is increased, while saving costs from reduced demands on city water.

Rainwater is relatively clean as it falls on our roof. If properly collected and stored, very little filtration is needed, resulting in a clean, viable source of water for irrigation with less threat to our environment. Following conservative landscaping methods using swales, rain gardens, drought tolerant plantings, and permeable surfaces, irrigation demands can be reduced – allowing for a cost effective means of irrigation. Even more cost savings can be achieved by including toilet flushing in the rainwater system design.

Both commercial and residential developers can benefit from rainwater harvesting systems intended for irrigation. Cost savings, water quality, and environmental protection are all positive outcomes for the developer and community. Being known in the community as a business or residence that cares about our environment and its resources is often admired by customers and friends. Future generations need for us to practice conservation now to ensure safe, sustainable water sources.  Rainwater collection can be part of this commitment.

Commercial Rainwater Harvesting, Rainwater Catchment

Water Conservation Through Rainwater Collection

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Federal Way Washdown_RainBankLLC_webThe most common use of rainwater collection is for non potable use. Irrigation, water features, wash down, toilet, and laundry are all non potable uses that can have a positive effect on water conservation. A properly designed and installed rainwater collection system will provide enough water to support these desired uses with less impact on our water supply.

Rainwater is essentially free of pollution, so it can be stored without much more than screening. Storage can be underground, above ground, metal, plastic, or fiberglass. If irrigation is the desired use, keep in mind that approximately .623 gallons per sq ft of planting, per week is required for the healthy growth of plants, therefore storage volumes can be a concern in design due to space and costs. Conveyance can be gravity if there is enough head. Head is .4 lbs per foot of elevation. A pressure pump might be necessary to achieve the desired pressure needed. Sediment filtration for a simple irrigation system should be all that is needed to ensure emitters and soaker hoses perform as expected.

Water features such as fountains can recirculate the water being used, so very little storage would be required. Sediment and carbon filtration would be needed to keep pumps and nozzles working properly. A carbon filter would be helpful to keep odor to a minimum.

Wash down facilities can use rainwater collection and save money on their water bills by using rainwater collection as the rinse water. With enough storage, a large fleet can be washed with recycled wash water and rinsed with collected rainwater. Again, sediment and carbon filtration would be the only filtration needed. Wash down of equipment, whether construction or farming, can benefit from rainwater collection.

Toilet and laundry facilities for residential and commercial applications are becoming more popular with new construction. Rather than infiltration, which is mandated, why not use that water. Simple pumping and filtration of stored water is all the treatment needed. A return on investment can be achieved within a few years.

There are a wide range of uses for rainwater collection. With a little bit of imagination you might come up with a use for rainwater collection that could save you money.