By State › Colorado
Colorado: Laws & Legal Considerations
Download all of Colorado as PDF PrintRainwater harvesting: legal only recently, and still restricted for some properties
Every other state covered on this site treats rainwater as essentially unclaimed until you catch it. Colorado is the exception: under strict prior appropriation, rainwater has historically been treated as already legally spoken for.
| Rule | Colorado |
|---|---|
| Underlying legal theory | Under prior appropriation, rainwater is considered tributary water that senior water rights holders are already entitled to; collecting it could interfere with their allocation |
| Standard residential rain barrels | Legal since a 2016 law, for single-family homes or buildings with 4 or fewer units, collecting from a rooftop for outdoor, non-potable use |
| Rural properties on an exempt well | Rainwater harvesting is legal only with a Precipitation Collection System Permit from the Colorado Division of Water Resources, under a 2009 law (SB 09-080) |
| Larger or commercial systems | Generally require an augmentation plan or other water court approval to avoid interfering with senior water rights |
Why Colorado is a genuine outlier among every state covered on this site
In every other state covered here, the question is simply whether a permit is needed, not whether the underlying activity is legal at all. Colorado rainwater harvesting was effectively illegal for ordinary residents until relatively recently, specifically because the state’s water law treats every drop as already allocated to someone. The 2016 rain barrel law and 2009 rural exempt-well law were targeted exceptions carved out of that default rule, not a general legalization.
Where to find it: the Colorado Division of Water Resources (dwr.colorado.gov) administers rainwater collection rules and permits.
Water rights: prior appropriation, the doctrine’s original home
Colorado is where the American prior appropriation doctrine was established in the 19th century, during the mining and agricultural booms, and its waterways are frequently over-appropriated today.
| Concept | How it works in Colorado |
|---|---|
| Governing principle | "First in time, first in right": the oldest water right on a given source has priority over newer rights |
| Practical effect | Many Colorado waterways are already fully allocated among existing right holders, which is exactly why new uses, including rainwater collection, can require special legal accommodation |
Where to find it: the Colorado Division of Water Resources administers water rights statewide; Colorado’s water courts adjudicate disputes and augmentation plans.
Concealed carry: training requirement increased in 2025
Colorado requires a Concealed Handgun Permit, and its training requirement recently increased.
| Requirement | Detail |
|---|---|
| Standard | Shall-issue through the county Sheriff's office |
| Minimum age | 21 |
| Training required (since July 1, 2025) | 8 hours, including a live-fire exercise and a written competency exam |
| Renewal | A 2-hour refresher course including 50 rounds of live fire and a written test |
Sources
- Colorado rainwater harvesting law history and current rules: Blue Barrel Systems; Colorado Division of Water Resources
- Colorado prior appropriation doctrine: Colorado State Engineer’s Office
- Colorado concealed handgun permit training requirements: HB24-1174; Have Gun Will Train Colorado