Rainwater Harvesting: Where Value and Cost Collide

20 August 2019

Rainwater harvesting is a practical and attractive tool for water conservation and to provide critical water supplies in disconnected or under-serviced communities. For areas with centralized water distribution systems, a harvesting system may be built to save water or span interruptions, but never to save money. This is due primarily to the pricing of centrally supplied water, where under-pricing or subsidies typically render the harvesting system significantly uncompetitive from a cost standpoint, making the return-on-investment of these alternate water supplies unattractive to most project investors. The paradox is the value: when a water supply is cut off or depleted, the value of water goes asymptotic. When centralized water is available, the harvesting system makes no sense financially. 

Philip Reidy, a registered professional engineer in the United States specializing in rainwater harvesting, discussed the cost metrics associated with fully functional rainwater harvesting systems, presented cost comparisons with other water supplies and presented efficacy analyses to demonstrate climate conditions that make them viable as stand-alone systems.

Program and Learning Materials: 
Date Session / Activity Presentation Material Speaker(s)
20 Aug 2019 Presentation Rainwater Harvesting: Where Value and Cost Collide
Philip Reidy, a registered professional engineer in the United States specializing in rainwater harvesting, discussed the cost metrics associated...
Philip Reidy


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