In most cities, rainwater does little more than create traffic or puddles, and is left to flow into gutters and ultimately, into storm-water drainage systems. This is noteworthy only because water is such a scarce and critical resource. In the US alone there are at least 36 States in which the lack of water is a genuine problem. According to the NRDC “rainwater collection systems on just half of the available rooftop space could supply between 21 and 75 percent of annual water needs [and] would also save residents a combined $90 billion in municipal water fees. (As a bonus, rainwater collection also reduces the amount of polluted runoff that flows into lakes, rivers and oceans.)” . So why don’t more poeple collect rainwater and more cities use it? There are lots of reasons, and some as simple as basic laziness or lack of knowledge. But in some places there are actual regulatory obstacles to residents seizing upon this money-saving and green opportunity. In some municipalities, rainwater in its untreated form is only permitted to be used for certain outdoor, non-potable functions, like lawn-watering and other irrigation uses. There are exceptions. Portland Oregon has created multiple standards and processes for the use of rainwater.
“Using purified potable water for purposes like flushing toilets or irrigating landscape is a waste of a valuable resource. Portland residents are asking more questions about the role of conservation in extending the supply of drinking water. Stored water can substitute for piped drinking water for many uses where a high level of purity is not required.”
For cities there are more strategic steps they should take to begin seizing the opportunity of rainwater as a conservation device, stem against storm-water contamination and replacements of city water for normal non-potable uses like toilet-flushing, irrigation and some cleaning. The first thing for cities to do is to adopt a clear set of guidelines for the use and treatment of rainwater. Here are the recommendations of the EPA:
- “Adopt stormwater pollution control standards that require on-site volume retention and allow rainwater harvesting and reuse, with appropriate health and safety standards, to be used to meet that requirement, thereby creating an incentive for on-site capture
- Adopt standards that require or promote rainwater harvesting and/or water efficiency
- Review building, health, and plumbing codes for barriers to capturing or reusing rainwater
- Provide incentives for decreasing storm-water runoff and promoting water conservation
- Require use of rainwater harvesting and reuse on all public properties”