The effort to legalize use of rain barrels in Colorado appeared to have broken out of its longtime logjam Monday.

Democrats in the state House allowed two GOP amendments meant to ease concerns over rain barrels and their place within state water law.

One amendment makes it clear that having a rain barrel is not a water right, and the other involves the state monitoring the impact of rain barrels on water rights.

“We’ve come a long way,” state Rep. J. Paul Brown, a Republican from Ignacio, said of the compromise. “Property rights are important. The Fifth Amendment of the Constitution establishes property rights, and water rights are a property right.”

Rain barrel legislation failed last year over concerns that using them would violate the rights of senior holders of water claims. Although the water lost to downstream water-rights holders is expected to be small, rain-barrel opponents argued the principle of water law was at stake.

Colorado is the only state with an outright ban on residential rain barrels. The proposed law would allow up to two 55-gallon rain barrels to collect water to be used on a resident’s lawn or garden.

Most Republicans in the House sided with Democrats on a voice vote Monday. The measure still has to pass a roll-call tally in the chamber before moving to the Republican-led Senate.

The two amendments to House Bill 1005 reflect the concerns expressed by Sen. Jerry Sonnenberg, a Republican from Sterling. Sonnenberg said last week the two points — recognition of prior-appropriation and state stewardship of the practice — had to be addressed before he could support the bill. Sonnenberg bottled up a similar bill in the Senate last year.

He said Monday the bill is “much, much, much better,” but he still wants to hear from the state engineer’s office about how the measure would be policed and whether rain barrel use could be suspended if there is a shortage of water in the rivers for those holding water rights.

“I like the direction we’re headed in, but I don’t think we’re all the way there yet,” he said.

“People out there in our communities, they want this,” Rep. Jessie Danielson, a Democrat from Wheat Ridge who has sponsored the measure the past two sessions, told fellow legislators before Monday’s vote.

“They want the ability to use a rain barrel to collect a little water to water their tomatoes.”

Joey Bunch: 303-954-1174, jbunch@denverpost.com or @joeybunch