DENVER (AP) – New research shows floods like the one that ransacked northern Colorado two years ago, killing 10 people, might be more common than previously thought – and that could require more homeowners to get flood insurance and trigger more stringent construction rules.
The September 2013 flood caused $3 billion in damage to neighborhoods, highways, farms and oilfields. Nearly 2,000 homes were damaged or destroyed, many in small mountain towns.
Early, rough estimates of the flood indicated it was a 1-in-500 event, meaning the chances of such a deluge in any one year are 1 in 500.
But recently completed studies of the Big Thompson River, St. Vrain Creek and other hard-hit waterways show it was mostly a 1-in-100 event, said Kevin Houck, chief of watershed and flood protection for the Colorado Water Conservation Board.
If a 1-in-100 flood can cause that much havoc, then homes, roads and other infrastructure are more vulnerable than previously believed, he said.