Against a backdrop of California experiencing the worst drought in its history and the U.S. Supreme Court having before it an interstate water dispute, where Florida seeks an equitable apportionment of the waters of the Chattahoochee and Flint Rivers over the claims of upstream Georgia, the issue of “who owns the rain” is of national importance.

Collecting rain and using it for a desired purpose on one’s own property should no longer violate laws. And the government should not take the rain falling on private property without just compensation.  

In point of fact, laws like the City of Tucson Ordinance 10597 of 2008 that require a minimum of 50% of water used for landscaping on new commercial properties be from collected rainwater on the site, may be the way of the future.

A simple and effective way to increase potable water supply and to decrease demand on stressed freshwater resources is collecting and using the rain allowing the free market to control water.

For millennia civilizations have recognized benefits of collecting the rain. Many ancient Roman homes had small cisterns to augment water supply from the aqueduct system. Rain barrels were once common across America both on farms and in towns. But centralized water infrastructure of the 20th century with the associated new laws to buttress it, the 19th century federal government claim that it controls all navigable water and unconstitutional state claims to land beneath watercourses, all made collecting rain illegal.

Water law in the western U.S. is governed by the “prior appropriation” doctrine. The details vary from state to state, but the first person to take a quantity from a water source for a beneficial use has the right to the continued use of that quantity of water. Water law in the eastern U.S. generally recognizes “riparian rights” where landowners whose property abuts a body of water have the right to make reasonable use of the water and if there is not enough water to satisfy all users, allotments are generally fixed in proportion to frontage on the water course. The difficulty under both schemes of water law was articulated by Utah Supreme Court Chief Justice Wolfe,

“All rain and snow water belongs to the public regardless of whose land it falls upon. Like all fugitive substances, it can belong to no one else except the public.” McNaughton v. Eaton, 1952 

Governments from Maryland to Colorado now regularly take the position that collecting precipitation is not legal, as a diversion of rainwater before it enters a water course. Maryland has the most stringent storm water (i.e., rain) regulation in the nation and even taxes the rain (by square foot). The Colorado legislature made clear it was illegal to capture rainwater off of one’s rooftop, as it infringed on the supply of senior water rights holders downstream, when in 2009 the state authorized certain limited exemptions approved by the State Engineer on residential roofs where no municipal water supply is provided.

However, collecting the rain has been legal in Utah since May 11, 2010, the effective date of Senate Bill 32 that provides “for the collection and use of precipitation without obtaining a water right” (storing up to 200 gallons above ground or 2,500 underground) after registering on the Division of Water Rights.

Today the City of Albuquerque Water Utilities Authority offers rebates of $1.50 per square foot for desert friendly landscaping and rebates of up to $150 on rain barrels, in spite of New Mexico law, including a policy of the State Engineer, “the collection of water … should not reduce the amount of runoff that would have occurred from the site in its natural, pre-development state.”

Collecting rain and using it for a desired purpose on one’s own property should no longer violate the law. Utah’s decriminalizing precipitation collection may be a model for the nation. Tucson may have gone too far in mandating rain collection for landscaping. But is it too farfetched to imagine government increasing potable water by not only making it legal but even offering incentives, like Albuquerque, for collecting rain?