In a matter of half an hour, Bear Creek, the typically tiny stream that runs along Table Mesa near the intersection with Broadway, went from brimming at its banks to spilling over them and flooding Table Mesa. Shoppers at the nearby King Soopers, stocking up on food but finding the shelves already bare of bottled water, had to navigate a foot or more of water to exit the parking lot. The bridge allowing westbound traffic to turn into the grocery store was overtopped and soon blocked by a police car. Emergency and city maintenance vehicles were already at the busy intersection, where manhole covers had been lifted up by gushing water and the Bear Creek bike path had spent the entire day submerged.
By 6 p.m., the intersection of Table Mesa and Broadway joined a long list of closed streets across the county that included all the canyons and major thoroughfares through Longmont, leaving the city bisected. Table Mesa was, of course, just one of many streets flooded as Boulder weathers the long-awaited 100-year-flood, and Boulder isn’t even the worst of the towns hit in the county. Highways in and out of town were closed later that evening, including highways 93 and 36, which was, according to the Sheriff’s scanner, under two feet of water.
North of Boulder, Lyons was cutoff by water and road damage, and the flooding
St. Vrain River took out a bridge through town on Thursday afternoon, limiting
emergency personnel’s access to stranded residents. The music venue Planet
Bluegrass, which had a concert scheduled for Friday evening, was utterly
Farther downriver, the St. Vrain was dividing the town of Longmont into islands. City Manager Harold Dominguez declared a state of emergency at just before 5 a.m. Thursday morning. Neighborhoods along the St. Vrain River were evacuated early Thursday morning.
Roads to Jamestown were wiped out, preventing access to and from the mountain hamlet, where one mudslide had already buried the home of a resident.
That resident, Joey Howless, was still missing as of Thursday evening, the Daily Camera reports, his home buried under 12 feet of rock, mud and debris. There is also a confirmed death in Jamestown, as well as one in Boulder and one in Colorado Springs. Sheriff Joe Pelle has said more fatalities in Boulder County are expected.
As of Thursday afternoon, when rainfall picked up again, 8 inches of rain had fallen in 24 hours over the Front Range from Colorado Springs to Fort Collins. Pelle advised residents to stay off the road Friday to avoid the dangerous conditions and leave room for emergency responders. Flooding was reported as far south as Manitou Springs, which has recently weathered debris-heavy flash floods in the wake of the forest fires there. The Big Thompson River in Loveland was flooding Loveland as well.
U.S. Geological Survey crews measured Boulder Creek running at a record-setting 4,500 cubic feet per second, topping the previous record of 2,050 cfs by more than half. (Access to current flood and high flow conditions can be found at the USGS WaterWatch website.)
In the afternoon update from Boulder County, officials announced that all canyons in the county were closed due to road damage and debris, 12 dams had overtopped and people were stranded in homes and vehicles. One person had been reported dead, and one person was missing. Communication with Jamestown residents was limited to radio, according to the county, and phone service in Allenspark was limited to Allenspark.
In Boulder, Mariposa, Hawthorn and Linden streets were showing road erosion and debris. City Manager Jane Brautigam, having declared the city in a state of emergency, had signed emergency rules to close the airport and all open space until further notice.
Boulder County was advising residents in Lyons and those with wells under standing water to assume their water had been contaminated and boil it before drinking. Details are available here. Water in the city of Boulder was still expected to be safe, as long as residents had had an uninterrupted water source and no discoloration.
Scanner reports in the evening were indicating that an electrical pole had caught fire and emergency personnel were unable to complete wellness checks because county roads were impassable. Xcel Energy had crews working to preserve gas and electrical access for residents, but gas in particular had been impacted. Boulder Valley Humane Society was taking dogs, cats and other small animals from residents facing an evacuation emergency. The Red Cross had established an emergency shelter at the YMCA of Boulder Valley at 2850 Mapleton Ave.
Ongoing flooding conditions are expected to continue throughout the night. All Boulder County administrative offices will be closed on Friday, Sept. 13, and the Office of Emergency Management recommended against traveling through Boulder. The National Weather Service had forecast steady rain through Friday, Sept. 13 and until 12 a.m. Saturday.
A map of flood warnings and hazards is available here.