Category Archives: Residential Rainwater Collection

Rainwater Catchment, Residential Rainwater Collection

Rainwater Collection for Potable Use in an Urban Environment

seattle-skylineSupplementary whole-house use of rainwater in an urban environment is more complex than collecting for potable use in a rural environment. In a rural environment, there is typically more room for storage, allowing the homeowner to store more water than that in an urban setting.

The larger question, however, is – what is landing on my roof and how do I know my collected water will be safe to drink?

In a rural setting, organics are what you need to filter out before the water is to be disinfected and considered potable. A sediment filter, followed by a carbon filter prior to ultraviolet disinfection can achieve this. Bird droppings are the primary concern in this situation.

In an urban environment, other constituents coming in contact with your roof may need to be addressed. Consider where your home is located. Environmental considerations such as automobile and truck emissions can have an impact on your roof runoff and must be removed with proper filtration. Pesticide use is more likely to be encountered in an urban setting than a rural environment. Simple sampling and laboratory testing should be conducted of raw water so proper filtration can be used to eliminate possible contaminants.

Urban potable usage of roof top collected water can be achieved with the proper filtration as with any rural potable system as long as the right filtration is used.

Photo: Julie Gentry

Rainwater Catchment, Residential Rainwater Collection

How Can Rainwater Harvesting Benefit our Cities?

How Can Rainwater Harvesting Benefit our Cities?

Storm water runoff is a major cause of water pollution in urban areas, which is why  we ask the question: How can rainwater harvesting benefit our cities?

When rain falls in undeveloped areas, the water is absorbed and filtered by soil and vegetation. Not so in urban environments. Streets, parking lots and buildings are impervious surfaces and do not allow the natural process of infiltration. In most urban areas, storm water is drained through collection systems and discharged into our waterways. This storm water carries oils, bacteria, heavy metals and other pollutants into the receiving water. The storm water overwhelms the sewer system and intentional releases of sewer into our waterways is conducted to prevent a spill onshore.

Seattle is mandated by the federal government to address its storm water and sewage releases into the Puget Sound. With higher density development, the “Green Stormwater Infrastructure” (GSI) was mandated to address storm water runoff with infiltration techniques such as bio swells, green roofs, infiltration planter boxes, including green parking areas and streets using permeable pavers. While these techniques are helping to reduce run off they do not address the increasing demands on our water resources.

Rainwater that is harvested collects and stores rainfall for future use. When designed and installed properly, it, too, helps reduce runoff while providing a viable source of water for irrigation, toilet and laundry facilities, and when filtrated and disinfected can be an alternative to city water for potable use.

With increased demands on centralized water systems from population growth, aging infrastructure, and increased costs to upgrade and maintain, rainwater harvesting for commercial and residential use is a viable and economical solution.

Mt. Rainier and the Puget Sound photo courtesy of Andrew E. Larsen.

Residential Rainwater Collection

Heron Hall – A Living Building Home

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Heron Hall - A Living Building HomeRainBank Rainwater Collection Systems principal Ken Blair is pleased to be a member of the Engineering and Consultant Team for Jason McLennan’s Heron Hall, a living building home on Bainbridge Island, WA.

McLennan is the CEO of the International Living Future Institute, a non profit organization behind the world’s most progressive and stringent green building guidance system.  He is the creator of the Living Building Challenge and heads Cascadia Green Building Council, the Pacific Northwest chapter for the US Green Building Council and the Canada Green Building Council.

Here, Jason speaks about the living building challenge:

For McLennan, “it’s not enough for architects, construction companies, and real estate management companies to focus on reducing their environmental impact.  The  time is right to be far more ambitious, think instead about recharging and replenishing our planet“, explains Jason.

Click here for more information about Heron Hall.