New Colorado housing developments could collect own water

April 2008

U.S. Water News Online

DENVER — New housing developments could get to test out an old-fashioned way of conserving water.

Recently, the Senate backed a bill that would let up to 10 new developments apply for permission to install cisterns to collect rainwater that drains off rooftops. The water would have to be used on lawns and gardens or to fight potential wildfires.

Democratic Sen. Chris Romer's proposal would let the developments try out the idea over the next three years. The aim is to measure whether the cisterns prevent a lot of water from flowing into rivers and streams or whether most of it would have been soaked up by the ground anyway.

Rural residents who aren't connected to a water supply would also be able to collect rainwater but they would be allowed to do it permanently.

A bill is needed to allow the practice because state water law says that all rainwater has be allowed to flow downstream to those who hold the rights to use a river's water.

Romer said collecting water in cisterns is common in other dry regions including New Mexico and in Australia and was used by the Anasazi, who lived in the Four Corners region until 1300.

“This is commonsense thinking that the Anasazi used to do before they were forced out of their community by drought,” said Romer, who originally wanted to install a cistern at the home he's building in an existing neighborhood in Denver. He said cisterns would have to be combined with other steps, including water conservation, to help prepare for future droughts.

Only new developments would be allowed to participate because authorities would have to look at how much water was absorbed by the

The measure now moves to the House.