Standards & Codes and Recent History of RWH


There are standards for installing rainwater catchment systems.


We have been trained in and follow ARCSA/ASPE/ANSI 63: Rainwater Catchment Systems (normative). There are also standards for Stormwater Harvesting System Design for Direct End-Use Applications, specifically ARCSA/ASPE/ANSI 78-2015. We also follow CSA B128 Series on non-potable systems. CSA/ICC Standard B805 is pending and will specifically address rainwater harvesting codes of practice in Canada. In some jurisdictions the IAMPO Green Plumbing and Mechanical Code Supplement, Uniform Plumbing Code can also be referenced.


Why do we follow these standards?


Many ideas have been put forward by governments, public health officials and others regarding the suitability of rainwater and stormwater for human use and consumption. It is only by the research, expertise and involvement of organizations like these that we can claim to understand what works and what has proven to be unreliable.



Historical Background on the Modern Evolution of RWH Best Practices


Rainwater catchment systems and rainwater harvesting have been done in the ancient world for millennia. In the modern world people have done demonstration projects and personal systems for decades. It is only very recently that standards have been created.



The International Rainwater Catchment Systems Association began



The American Rainwater Catchment Systems Association began


Germany developed the Fachvereinigung Betriebs- und Regenwassernutzung and became the Secretariat for the European Region in 2009. These associations came into being from the idea that “rainwater is not centralized, so why should we centralize the supply of it to people” (ERCSA, 2008)?



The International Rainwater Harvesting Alliance was created. It is based out of Geneva Switzerland. Their mandate is to promote rainwater harvesting as a valuable water resource and be part of the fulfilment of the UN Millennium Development Goals.



The Texas Manual on Rainwater Harvesting was written by the Texas Water Development Board Projects built around this included the Branch Municipal Utility District Recreation Centre. Storage capacity is 37,000 US gallons and the building is 10,000 square feet. Another project was the Lady Bird Johnson Wildflower Research Centre in Austin Texas that harvests 300,000 gallons of rainwater a year from 19,000 square feet of roof collection surface (Texas Water Dervelopment Board, 2005).



Australia started to look into formalizing rainwater harvesting practices in 2004. Yet it took till 2006 to establish its first Rainwater Tank Design and Installation Handbook under the mandate of Australian Rainwater Industry Development Group, now known as the Rainwater Harvesting Association of Australia.


Salt Spring Island, British Columbia Canada published its first Guide for Regulating the Installation of Rainwater Harvesting Systems – Potable and Non-potable Uses



Province of British Columbia published Beyond the Guidebook: Context for Rainwater Management and Green Infrastructure in British Columbia. focused on green infrastructure that is water-centric and founded on a natural systems approach. One of the major transitions in this program was to move from a stormwater focus to an “integrated and comprehensive perspective that is captured by the term rainwater management” (Inter-Governmental Partnership, 2007)



The City of Tucson Arizona passes a new ordinance requiring commercial buildings to have no less than 50% of their water required for landscaping purposes to be supplied by rainwater (Mayor & Council Tucson AZ, 2008).



British Standard BS 8515:2009 BSI Rainwater harvesting systems – Code of Practice was developed.

Georgia State, USA publishes its first Rainwater Harvesting Guidelines for non-potable uses under the plumbing code (Georgia State Guidelines Committee, 2009).



The London Olympics embraces a 40% municipal water use reduction target. They used half of the 13,000 meter roof as a harvesting surface for supplying water for toilet flushing, and landscape irrigation. The system is augmented by a black water recovery system. The biggest lesson was that rainwater harvesting needs to be assessed in a broader context. (Olympic delivery authority, 2011). This is why we take a whole water approach!


Primer on Rainwater Management in an Urban Watershed Context written under the umbrella of the Water Sustainability Action Plan for British Columbia. It recognized the importance of limiting negative effects on streams. Greater runoff from increased impermeable surfaces, loss of the riparian corridors from excess sedimentation, aquatic habitat degradation, and decreased water quality were all issues that integrated rainwater management programs could improve (Water Sustainability Action Plan, 2011).

Asia Development Bank Headquarters in Manila, Philippines is recognized by LEED for water conservation and green building initiatives in an existing facility that included using rainwater for the cooling tower, landscaping and washing purposes. They also added their own on-site treatment plant to achieve 100% utilization of non-potable and treated water. Runoff volumes have decreased by 30%. The facility covers 6.5 hectares and holds about 3,500 employees. 407,000 litres of water is retained in the system (ADB, 2012).



The Regional District of Nanaimo, British Columbia Canada published Rainwater Harvesting Best Practice Guidebook (Burgess, 2012).



Primer on Land Development Process in BC Industry Standards of Practice in Implementing Rainwater Management – Integrating the Site with the Watershed, Stream and Aquifer was written under the IREI [Inter-Regional Education Initiative]



In July 2015 at the Addis Ababa meeting prior to Paris, a declaration was made calling on policy makers, donors, and practitioners to acknowledge the positive benefits rainwater harvesting has on the water supply, climate resilience, food security and well-being (RAIN, SearNet, WAC, AgWA, IFAD, waterhealth, 2015). These are a few of the international steps being taken to integrate all water sources under one umbrella.


The Metro Manila Development Committee put forward a bill requiring all new commercial buildings in Metro Manila to install rainwater harvesting facilities.


Australia announces that rainwater harvesting has gone ‘mainstream’. Estimate national storage capacity is 8 billion litres, however those tanks can fill up to 5 times a year. It is estimate that about 156 billion litres of rainwater is being used in the nation as of 2014. The Australian Capital Territories account for 1% of the national rainwater consumption use (Smit, 2015).


ARCSA has just published its Rainwater Harvesting Manual in 2015. It is targeted for all jurisdictions utilizing Standard 63, but is easily adapted to local regulatory practices.






Are you facing an unsafe or inadequate water supply, moratoriums, or simply need more water than you have at present?

AloPluvia provides integrated, scalable, best practices to solve those ‘wicked water problems’ using a whole water approach. Our innovative, research driven solutions provide real answers.


Integrated water resource management looks at ways to limit the effects of excess runoff on surface water health and increase the renewal of groundwater supplies. It considers ALL water resources not just surface and groundwater, but WHOLE WATER.

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