Kathleen Curry and Jim Isgar plan to introduce a bill to allow rural property owners to utilize rainwater catchments on a small scale. The bill will limit the catchments to properties served by an "exempt well," that is, a well that is allowed to pump regardless of priority because the amount of water produced is so small that it is assumed that no senior rights holder will be harmed.
Apparently, there was also a bill last spring that allows Colorado to start examining how best to utilize "rain harvesting" as part of an overall water conservation strategy.