My eco- and money-conscious friends and I have had many discussions about whether you can legally use rain barrels to collect precipitation for watering landscapes in Colorado. Friends that have transplanted from moist regions of the country find it hard to believe that this simple act is against the law. Some have heard that legislation was recently passed to allow rain collection. So, what’s the deal? Are rain barrels illegal?

Colorado is one of only two states (Hawaii is the other) in which all water flows out of the state. Water has always been very important for our state development but it has also been crucial for states downstream. All water that is in – and eventually flows out of – Colorado is already owned by someone else. Welcome to the overwhelmingly complicated web of water rights in our state.

Every drop of rain that falls from the heavens is already accounted for as soon as it hits my barren front yard. Storm water is owned a few times over by junior and senior water rights holders. Going back to 4th grade science, rain congregates and flows into rivers and creeks via the stormwater infrastructure. It all ends up in our major rivers like the Arkansas, which farmers and cities all the way to the Mississippi depend on. Precipitation can also percolate into the groundwater system that supplies wells that many property owners use for drinking water and irrigation. “Rainwater harvesting,” as it’s called, diverts this water out of the normal system by capturing it in barrels for later use. Not too big of a deal if a few people do it, but if everyone collected rain, the rivers could be altered. Therefore, according to the Colorado Division of Water Resources, rain collection is illegal.