Collecting Rainwater

“The quality of mercy is not strained; It droppeth as the gentle rain from heaven Upon the place beneath. It is twice blessed- It blesseth him that gives, and him that takes.” - William Shakespeare, The Merchant of Venice

A rain barrel or two may seem like the perfect solution for watering the garden without waste or adding to your water bill. But before you build your rainwater harvesting system, you should make sure that it’s legal to do so. “There are three states that say the water that falls from the sky belongs to them, not to just anyone.”
See [ExpertSure.com] and [Popular Mechanics] In Utah any diversion and retention of rainwater requires a “water rights” permit. “You don’t have a right to divert and use the waters in streams, springs, groundwater or any other source [i.e. rain] just because they are on your land, like they do back east. In Utah, a water right (right to use the waters of the public) is obtained by application to, and approval of the application by the State Engineer.” [Utah.gov]


Rain barrels are illegal in Colorado. “Colorado Water Law requires that precipitation fall to the ground, run off and into the river of the watershed where it fell. Because rights to water are legally allocated in this state, an individual may not capture and use water to which he/she does not have a right.” [Colorado Water Law] In addition, “Denver water customers are not permitted to take their bath or laundry water (commonly referred to as gray water) and dump it on their outdoor plants or garden.” [Colorado State Board of Health Guidelines]


Rain collecting is illegal in Washington state BUT legal in the city of Seattle. “The City of Seattle, … obtained a citywide water-right permit to ensure the legality of water harvesting efforts.” [epa.gov]
In contrast, rain collecting will be REQUIRED in Tucson, Arizona. Beginning June 1, 2010,
50% of a commercial property’s irrigation water for landscaping must be supplied from rainwater harvesting.


We use a lot of water on our yards and gardens. Even Americans, who live in the middle of deserts, want green lawns! I recall flying into Dallas, Texas and noticing the color change from the pale yellow of desert scrub brush to suburb bright green grass. Arizona was once the destination of choice for asthma and allergy suffers for its dry, pollen free air. But now the vast expanse of residential pools, lawns and gardens has increased the humidity and the pollen count of major cities.


Bottom Line
If you don’t live in Utah, Colorado, or Washington (outside of Seattle) then collecting rainwater can save you money and help conserve water resources. According to the EPA, “The U.S. uses more water per capita than any other country.”
The easiest collection system is putting a rain barrel beneath your rain gutter downspout. See 3 Cheap DIY Rain Barrels That Actually Look Nice!
Or How to Build a Rainwater Collection System
Or Poor Man’s Guide to Rain Barrels
We tried this at home but encountered some problems:

1. If not tightly sealed, mosquitoes and other bugs will breed in the water
2. If not drained for the winter, the water may freeze, expand and burst the container.
3. You need a plan for using the water or it just sits until #1 or #2 above occurs

Post Script
If you travel to NYC you may notice water tanks on the tops of many buildings. This is not rainwater collecting. Since the 1800s, to prevent loss of water pressure for fighting building fires, New York City has required that all buildings higher than 6 stories [now 80 feet] be equipped with a rooftop water tower. See New York Rooftop Water Tanks for photos and a history.