MAIL: Rainwater Legalities


I thoroughly enjoyed Stephen Hren’s informative and detailed article about rainwater harvesting in HP149. But here in my home state of Colorado, collecting rainwater counts as theft of property from downstream water-rights owners, and can result in fines of $500 every day that the rainwater collection system is in operation. Even placing a bucket under your shower to gather the first couple of gallons of cold water before it heats up and you jump in, and then watering your outdoor garden with it, is often illegal—no matter where the water comes from. As they say ‘round these parts, “Whiskey’s for drinkin’ and water’s for fightin’.”

In 2009, Colorado eased up a bit on the law after a study revealed that 97% of rooftop rainwater never makes it into streams or aquifers anyway, but rainwater harvesting is still not legal for most Coloradoans. If water service is available from a utility, no matter the distance or cost to run it to your home, you can’t use rainwater or snowmelt from your roof, driveway, or yard—for anything. If you own more than 35 acres and have a special well permit, you might be allowed to use rooftop rainwater outside your home for a very few, specific uses. If your rural property is less than 35 acres and you don’t have city water service, you are now allowed to use roof-harvested rainwater inside the home, but not outside for a hot tub, vegetable or flower garden, greenhouse, aquaculture, trees, or animals.

And in all cases under the new law, a permit from the state Division of Water Resources is required for any rainwater harvesting. Even composting toilets and water storage for fire protection are tricky legal areas; composting toilets don’t put wastewater back into the ground, and fire-protection cisterns may have to be locked so that only firefighters can draw water from them.

Of course, it’s unlikely that your grandmother in Denver will be fined or jailed for watering her petunias and tomatoes from the rain barrel under her downspout. State regulators claim to focus on violators who try to store large amounts of rainwater for irrigation and livestock. And Colorado’s water-rights laws are not some new bureaucratic affront to our personal freedoms, but rather date from the era of presidents Abraham Lincoln through Ulysses S. Grant—before Colorado was even a state. In any case, though, tell grandma to watch her back. For more information, see

Dan Fink • Buckville Energy Consulting

Comments (2)

jasondemoe's picture

Rainwater harvesting is NOT illegal. It was heavily restricted in Colorado, Washington and Utah until 2009, but all three states have since relaxed their bans

Michael Welch's picture
Not sure about any other states, but CO's bill failed.
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