At a recent holiday gathering I was once again asked " Why would you drink rainwater ? After all, rainwater picks up all kinds of pollutants in the air and from your roof. It is just so dirty and would require elaborate filtration and maintenance. Municipal water is tested and so much cleaner." Well, my response was that when you compare the water data tests it shows quite a different story.
The following table compares drinking water from the municipal source and treated rainwater. The municipal water is directly collected from the tap and the rainwater is collected from an asphalt shingle roof, stored and then treated.
The rainwater treatment process is designed to exceed EPA drinking water standards and includes:
300 micron downspout filtration * first flush * aeration * 20 micron filtration * 5 micron filtration * .5 micron charcoal block * UV light
This rainwater treatment process might seem elaborate but in reality is quite simple. Maintenance is easily managed by the system owner which includes filter cleaning and UV light replacement. The UV light unit includes a malfunction alarm.
The table below proves rainwater can be a cleaner drinking water source. The bottom line is that water quality is higher if collected before it hits the ground. Water quality in lakes and rivers can have extreme fluctuations based on rain events, storm water pollution, and other environmental factors.