Boise Fire officials say the cold weather helped keep fuel vapors from spreading when the valve systems of a large gasoline storage tank failed on Curtis Road Wednesday morning.

As many as 5,000 gallons of gasoline got out of the tank, one of several in the 700 block of Curtis Road, just south of Emerald Street, just after 7 a.m. Wednesday.

The fuel spill did not get to the street as it was contained in a trench around the tank, which is installed for that purpose, Boise Fire officials said.

Fire officials say a mechanical failure caused a valve to fail but workers were able to close the isolation valves quickly once it was discovered. The gas spill is contained and clean-up crews were on their way to clean up the spill at 9 a.m.

The public — and haz mat crews — caught a break thanks to cold weather, which kept the fumes from spreading and helped crews contain the spill quickly, officials said.