Category Archives: Rainwater Catchment

Rainwater Catchment

Construction Starts on Bainbridge Island’s Heron Hall


Close-up of a worn, metallic fountain pen nib on a black surface.RainBank Rainwater Systems of Seattle is excited to begin building the rainwater collection system for Heron Hall, on Bainbridge Island.

Heron Hall is the creation of Jason McLennan, who’s bio describes him as: Considered one of the most influential individuals in the green building movement today and the recipient of the prestigious Buckminster Fuller Prize, Jason F. McLennan’s work has made a pivotal impact on the shape and direction of green building in the United States and Canada and he is a much sought after designer, presenter and consultant on a wide variety of green building and sustainability topics around the world. McLennan serves as the CEO of McLennan Design and is the Founder and Chairman of the International Living Future Institute – a leading NGO that focuses on the transformation to a world that is socially just, culturally rich and ecologically restorative.

An Ashoka Fellow, Jason is the founder and creator of theLiving Building Challenge,widely considered the world’s most progressive and stringent green building program. He is the author of five books;The Philosophy of Sustainable Design, The Dumb Architect’s Guide to Glazing Selection, The Ecological Engineer, ZugunruheandTransformational Thought.

RainBank worked with 2020 Engineering’s Mark Buehrer, PE on design of the rainwater collection system, whichwill be the sole source of water for this residence, designedto be one of the world’s greenest homes.

Please watch the video below, and follow along with RainBank’s and Jason’s blogs on the construction of this magnificent home that will be a standard of the Living BuildingChallenge.

Rainwater Catchment, Sustainability

Helping Future Rainwater Harvesting Engineer


View through a circular metal structure to a cloudy sky.Future Rainwater Harvesting Engineer Seeks Help from RainBank

Seattle based RainBank Rainwater Systems receives many requests for information. Some questions come from homeowners building residential systems, others from architects, general contractors and engineers who may be interested in a commercial system design for toilet flushing or irrigation.

Recently we received an inquiry from a high school student in New Jersey interested in rainwater harvesting for a school project on water conservation. He was well prepared with a budget, total square foot of collection area, a plan of usage and most importantly, interest!

Hoping to harness hisenthusiasm, Chad Lindsly, RainBank Engineering, worked with the student on this theoretical design with demand/supply calculations, collection/storage coefficients, conveyance, filtration, costs and return on investments, all through email. He actually instructed the student on how to design a system, while meeting the scopeof his school project. Between them, Chad and the student designed a sustainable, cost effective rainwater system that fell withinthe parameters of the school project’s criteria. The student is turning in his work today and we wish him the best.

RainBank Rainwater Systems has always been at the forefront ofthe advancement of conservation and sustainability education. Chad continues the tradition by paying it forward and taking the time to engage with a potential future engineer.

Rainwater Catchment

Building a Potable Rainwater Collection System


Close-up of a worn, metallic fountain pen nib on a black surface.There are several stages to building a successful, potable rainwater collection system. Here is an article originally published in June 2014, under the title Ultraviolet Light Disinfection For Rainwater Harvesting. (Also see “How to Build a Rainwater Collection System,partsone,two,three,four,five,six,sevenandeight.)

The final stage of treatment for a potable rainwater collection system is ultraviolet light disinfection (UV). Effectiveness of the UV system is determined bya few factors. First, pre-filtration, which includes a sediment filter and a carbon filter that need to be upstream of the UV. This will help ensure the clarity of water entering the UV chamber, enabling the UV rays to penetrate the water stream.

When UV energy is absorbed by the reproductive mechanisms of bacteria and viruses, the genetic material is “rearranged” and can no longer reproduce,with risk of disease eliminated.

There are 2 classifications of UV light determined by the dosage of the UV light itself, and a class “A” UV is the only class recommended for disinfection of rainwater collected from a rooftop.

TheAmerican Water Works Associationdescribes a class A ultraviolet system as an effective method of disinfection for water that is not determined safe to drink. A class B ultraviolet system is only effective for water already deemed safe to drink – such as a water source already treated with chlorine.

An alarm and or solenoid valve for system fail safe is always a good idea to include with your UV system. This method will shut down the system or sound an alarm if a sensor determines the water turbidity (clarity) is not sufficient for proper UV absorption.

Ultraviolet light is a natural, cost effective environmentally safe method of disinfecting drinking water as long as it is properly maintained and the bulb is changed according to manufacturer’s recommendations.

As always, before you take on a rainwater harvesting project, know the rules in your state, county and municipality. It helps to work with a RWC pro who can help you through the process, saving you time and money along the way, while also ensuring that the result is a functioning and safe water collection system that will serve you for many years.