A mountain, a river , a reservoir, a field, a street, a roof, a gutter all have something in common….they receive rain and can all be considered rain catchers. Rain is free and catching it can have important implications for food and energy production, environmental uses, water supply , and waste water management. Harvesting rain water is usually thought of as water for irrigation, and not so much as a waste water control strategy. This may change where flooding and combined sewer overflows are a problem.
The harvesting of rainwater has been around for at least 2,000 years, to supply both agricultural and domestic needs , in Syria and present day Israel.
Stress on our present water systems comes from the increase in demand due to population increases. climate change, reduced water sources, competing demands from agriculture , energy, and industry. Water and development experts are being forced to come up with new ways to source this valuable resource.
Consider in cities where surface run off and sewage water end up in the same place. Rainfall does not require treatment like sewage , but does put a burden on waste water treatment plants. Problems can arise when during periods of high rainfall waterways become contaminated by sewage/ rainwater overflows. Perhaps the harvesting of rainfall on a large scale can help alleviate this problem by reducing the amount of runoff going to the treatment plants.
Due to local variations in terms of rainfall amounts, demand, catchment area, price, and regulations we recognize rainwater harvesting won’t work everywhere. The Columbia Water Center has developed a tool to help determine the viability of rainwater harvesting. With the help of this tool it has been determined that harvesting of rainwater makes more sense in the Central and Eastern parts of the U.S. This information is useful at the local level to help officials decide if rainwater harvesting should be promoted and study the impact on run off.
In closing harvesting rainwater has been around for a long time. Israel even has this idea incorporated into their overall master plan. Harvesting rainwater is an emerging option that may have greater implications for us moving forward.