In commierado it’s illegal to capture rain water.
They’ve loosened up for people who have 35 acre plots. Still no good for people in towns though.
https://www.google.com/search?q=colorado+%22rainwater+collection%22&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&channel=sb