The Latest Absurdity in the Fight to Conserve Water: Making Rainwater Harvesting Illegal

A recent article in the Los Angeles Times described the latest absurdity in the never-ending search to quench the thirst for water: ownership of rainwater and, more precisely, the illegality of rainwater harvesting.  Residents and communities in parts of Colorado are turning to this ancient practice of collecting and storing rain to fulfill their domestic water needs, including flushing toilets and watering lawns.  Using this “grey” water, as it is called, relieves pressure on water resources and can be extremely efficient.

Many long-time water users, however, object to the practice.

These so-called water buffaloes argue that people who collect rainwater are taking away from their water by collecting the water before it has a chance to flow into a river from which they obtain water.  Effectively, they argue, the rainwater belongs to them – they own the rain that falls from the sky as part of their water allocation, even though 97 percent of the rainfall that falls on soil does not reach a river.   The bad news?  The law in Colorado stands behind those water buffaloes.

Like most states west of the one-hundredth meridian, Colorado follows the doctrine of prior appropriation to allocate water.   For all water uses that are non-domestic, a person must have a water right.  Water rights are assigned a priority date, which is the date that the water use was initiated.

Under prior appropriation, these senior water users – many of whom have rights dating back to the 1800’s – have priority in times of water shortages based on the date of their initiation.  Their water allocation is fulfilled before any junior users, who are often left with a nominal amount of water.  People who harvest rainwater are “interfering” with the priority system by jumping ahead of all the senior users, who have the first right to use the water. 

This dogmatic adherence to temporal priority blocks efforts to acquire water rights for newer or more efficient uses, such as in-stream conservation and recreation.  These uses, initiated relatively recently, will always be subordinate to older, more consumptive uses.  

Ownership of water has always been a tenuous proposition.  Water and water rights linger on the perimeter of traditional property rights, eluding the solid “property” categorization of items like land or salad bowls.  Individual water molecules cannot be marked or identified, and water is in constant motion, swirling below, above, and around the earth in the global hydrologic cycle.  More significantly, water is survival for the vast array of living creatures on this planet, so privatizing the world’s most precious liquid would necessarily create a divide between haves and have-nots.   

Whether or not water is definitively property has great legal implications for constitutional and civil claims, and courts have not given clear or consistent guidance.  If, for example, water is considered a property right and the government required reduced water delivery to irrigators under the Endangered Species Act, those irrigators might have a valid claim for compensation under a Fifth Amendment takings claim.  CPR Member Scholar Dan Tarlock blogged about this specific issue here.  Categorizing water as a private property right also facilitates the commodification of water, which often ignores the common public interest in water quantity, quality, and viability.  

Many water rights are colored by the public trust doctrine, which holds that certain natural resources cannot be privately owned and instead must be held in trust by the government for the use and benefit of the public.  This doctrine, an inherent component of a water right, tends to support the argument that water is not a matter of private property.  As inexpensive supplies of water dwindle, how water is viewed as a private property will become increasingly important to water allocation and priorities.