Tag Archives: rainwater system design

Commercial Rainwater Harvesting, Rainwater Catchment, Residential Rainwater Collection

RainBank Rainwater Harvesting Systems in Seattle


Two palm trees, one healthy and one dried, displayed indoors.RainBank Rainwater Systems of Seattleis anARCSAaccredited designer, consultant, and installer of rainwater harvesting systemsfor both potable, and non-potable demands. Commercial and residential systems are designed and constructed to meet our customers’ specific needs.

RainBank will design, install and package systems from 2,500 gallons to 50,000 gallons.

RainBank’s customers are

  • Eco-friendlyhomeowners seeking to add rainwater collection or integrateinto plans for anew premiumorcustom built residence
  • Architects developing plans forpremium residential projects
  • High-endbuilding contractors specializing in custom builds
  • Commercial contractors where rainwater harvesting is a component tothe scope of the project

RainBank provides customers with an integrated, progressive and modern approach to sustainable, premium water systems.

RAINBANK SERVICES INCLUDE:

DESIGN:complete systems with performance specifications.

ENGINEERING& PERMITTING: to meetall legal requirements from county and state agencies; cost effective, faRow of rain barrels connected to a gutter system for water collection.st & hassle free.

INSTALLATION:includes onsite management & the “soup to nuts” installation of rainwater harvesting and storagesystems.

PRODUCTS: A rainwater system designed with WISY products requires minimal maintenance and never needs replacing. Never clean a filter basket or a tank again. Ever. (Come back often; we’re adding new product lines for 2016!)

CONSULTING:is available throughout the US Including Hawaii, for all rainwater harvesting & Class B water systems.

PACKAGING:Customized kits & blueprints for do-it-your-selfers, those in remote locations, tract housing developers and large companies. Use the form below to contact us aboutcustomized kits or other services.

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Rainwater Catchment

Planning a Rainwater Collection System

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A rustic house surrounded by tall trees and dense greenery.When planning a rainwater collection system, consideration of annual, monthly, intensity and frequency of rainfall must be taken into account. Precipitation information is generally available by most counties, state climatologists, the National Oceanographic and Atmospheric, Administration (NOAA) and the National Climatic Data Center.

Rainfall amounts in a given location can vary from month to month as well as intensity and frequency. Precipitation reports typically include snow as well as rainfall amounts. A history of rainfall amounts with consideration of a 50 or even a 100 year event are often required by the permitting agency to control overflow and runoff.

Rainfall intensity is measured in inches of rain per hour (IPH). Rainfall intensity will determine the choice of collection components and storage amounts. Although “first flush devices” are widely promoted by permitting agencies and some designers, they may not be the best option. If a given location has a low IPH, a first flush device may not be the best method of pre filtration upstream of storage.

Rainfall frequency can be obtained by a local climatologist and taken into consideration of storage and conveyance. Frequency of rainfall for a given area will help determine storage, as well as pipe size used for conveyance.

Rainfall return period is the historical data of a rainfall in a given location. While not a representation a specific time period, a return period determines the probability of an equal event in a given time. In other words an event of a 2-year return period has a 50% chance of occurring in any 1 year period.

Lastly, a maximum amount of dry days is critical in the design of a successful rainwater collection system. An historical account of dry periods is essential in determining storage capacities to get through the dry months.

Careful review of local rainfall data in determining size of storage, conveyance, and components is essential in a successful rainwater collection system.

Residential Rainwater Collection

Rainwater Systems Provide Years of Quality Domestic Use


A row of houses behind a field and trees under a clear sky.A well-designed and soundly constructed rainwater collection system, with scheduled ongoing maintenance, will provide years of quality domestic use.

RainBank Rainwater Systems has been providing safe, clean, reliable water for whole house usage for years. Recently, we went to Lopez Island to provide maintenance and inspections forsystems installed over a decade ago. RainBank was established on Lopez Island, WA, and it now has some of the longest running systems in the state. These systems were designed and constructed to provide whole house, potable water usage.

A row of houses behind a field and trees under a clear sky.San Juan County was the first county in Washington State to allow rainwater collection for potable use, due to salt water intrusion of wells like RainBank president, Ken Blair’s system. Low production and higher levels of fecal coliform or nitrates are other factors that have plagued wells in this area.

RainBank Rainwater Systems has been providing ongoing, scheduled maintenance for many of these customers since their installs, while other, do-it-yourself customers have observed and learned how to maintain their own systems. All of these rainwater systems are still providing a viable source of water for whole house usage.