A bill that would allow Colorado residents to legally put out rain barrels to catch water dripping from their roofs boiled down to a debate over precedent and "common sense" in the statehouse Friday.

The measure, letting residents put out a 100-gallon barrel and catch up to 600 gallons a year to use on their gardens, passed a narrow voice vote, and it appears to be in danger when a roll-call vote is held next week.

Colorado water law says water that falls on your roof isn't yours; it belongs to the system and ultimately downstream users who own a water right, said Rep. Don Coram, R-Montrose.

Rep. Jessie Danielson, D-Wheat Ridge, countered: "It still goes into the same ground it would if it came down the gutter and straight into the ground."