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Featuring the Brazilian Ball Pre-Filter System: A Case Study By Brock Dolman and Kate Lundquist

The following is the text and photos from a booklet written by the WATER Institute in 2008. Feel free to download this booklet and share the information widely. Click here to download a PDF of the resource list only. If you would like to support the continuation of this kind of work, consider making a donation to OAEC's WATER Institute.


We would like to thank the Compton Foundation, the Dean Witter Foundation, and the Panta Rhea Foundation for their generous support of this project.

OAEC’s WATER Institute was established to offer positive responses to the crisis of increasingly degraded water quality and diminishing water quantity. We promote a holistic and multidisciplinary understanding of healthy watersheds through our four interrelated program areas — Watershed Advocacy, Training, Education, and Research. For more information please visit www.oaecwater.org.

The Occidental Arts and Ecology Center (OAEC) is a nonprofit education and organizing center and organic farm in Northern California’s Sonoma County. Since 1994 OAEC has explored, educated about and implemented innovative and practical approaches to the pressing environmental and economic challenges of our day. For more information please visit www.oaec.org.


Fresh water is a precious and limited resource that nourishes innumerable life forms. As population pressures increase, the majority of communities around the world are facing decreasing supplies of fresh water in general and many lack access to potable water at all. This lack of access impacts human health around the globe as many die from water born diseases and related illnesses every year. For those who do have access to fresh water through private wells, springs or municipal systems, water quality can be compromised by naturally occurring heavy metals and imbalanced mineral loads or increasingly by toxic chemicals that contaminate groundwater supplies. Concerns have been raised over the potential impact that chlorine and chloramines found in municipally treated water have on human health as well.

There are others that are being impacted as well. As the demand for fresh water increases, this precious resource is being diverted, dammed, and extracted to the degree that a large number of watersheds, and the myriad species that rely upon the water supplied by them, are being put under strain and are being listed as impaired, threatened or endangered.

In those communities where access to fresh water is limited and watershed health is of concern, one viable “low-tech” solution is to build a roof water harvesting system. By creating the means to store water on site, using the existing rainfall as the source and infiltrating the grey water and remaining run-off, one can eliminate the need to draw from precious ground water supplies and avoid the high costs (economic and environmental) of hooking into centralized conveyance and treatment systems. Humans benefit from having a self sufficient, clean water supply that additionally provides fire protection and costs far less than bottled water. The ecosystem receives benefits from the reduced erosion, flooding and pollution caused by run-off and the reduction of demand on groundwater supplies.


The following is a list of websites, tax incentives, reports and publications for rainwater catchment systems legislation, policy guidelines, design and installation. The resources are listed alphabetically by country, then state, then city or publication title. It is our hope that citizens and policy makers will use this information to create policy language, pass initiatives and install rainwater catchment systems in their own cities, states and countries. Click here to download a PDF of this resource list only.



  • Gold Coast City Council – www.goldcoastwater.com.au/rainwatertanks This city council has created a Waterfuture Strategy to meet the water savings targets established by the Queensland State government in Dec. 2006 (see below). The Council mandates the installation of rainwater tanks for non-potable uses such as washing machines, toilets and outdoor uses on all new residential and commercial construction. This