July 31, 1976 Big Thompson Flood — @USGS

Big Thompson Flood, Colorado. Cabin lodged on a private bridge just below Drake, looking upstream. Photo by W. R. Hansen, August 13, 1976. Photo via the USGS.
Big Thompson Flood, Colorado. Cabin lodged on a private bridge just below Drake, looking upstream. Photo by W. R. Hansen, August 13, 1976. Photo via the USGS.

Click here to go to views the poster from the United States Geological Survey:

In the early evening of July 31, 1976 a large stationary thunderstorm released as much as 7.5 inches of rainfall in about an hour (about 12 inches in a few hours) in the upper reaches of the Big Thompson River drainage. This large amount of rainfall in such a short period of time produced a flash flood that caught residents and tourists by surprise. The immense volume of water that churned down the narrow Big Thompson Canyon scoured the river channel and destroyed everything in its path, including 418 homes, 52 businesses, numerous bridges, paved and unpaved roads, power and telephone lines, and many other structures. The tragedy claimed the lives of 144 people. Scores of other people narrowly escaped with their lives.

The Big Thompson flood ranks among the deadliest of Colorado’s recorded floods. It is one of several destructive floods in the United States that has shown the necessity of conducting research to determine the causes and effects of floods. The U.S. Geological Survey (USGS) conducts research and operates a Nationwide streamgage network to help understand and predict the magnitude and likelihood of large streamflow events such as the Big Thompson Flood. Such research and streamgage information are part of an ongoing USGS effort to reduce flood hazards and to increase public awareness.

After the September 2013 floods Allen Best wrote about being part of the disaster response in The Denver Post. It’s a good read. Here’s one passage:

I was at the Big Thompson disaster. I was living in Fort Collins then and was among scores of young men (sorry, women, those were different times) with strong backs who could be summoned in case of forest fires. My only fire was at an old sawmill site in the foothills. The joke was that one of us had set the fire because we were so desperate for minimum-wage work.

Then came July 31. It was hot that night in Fort Collins. It hadn’t rained a drop.

I was living above Gene’s Tavern, just two blocks from the Larimer County Courthouse. When the call came, I was at the sheriff’s office almost immediately. It was 9 p.m.

Being among the first at the command center at the Dam Store west of Loveland, near the mouth of Big Thompson Canyon, I was assigned to a pickup dispatched to look for people in the water near the turnoff to Masonville. Already, the river was out of its banks. From the darkness emerged a figure, dripping and confused. “I went fishing at Horsetooth (Reservoir) and was driving home and then there was all this water,” he sputtered. He was befuddled. So were we.

Our leader decided we’d best get out of there. From what I saw the next morning, that was an excellent decision. Water later covered the road there, too. I spent the night at the Dam Store as the water rose. Helicopters were dispatched, but there was little that could be done. Our lights revealed picnic baskets, beach balls and propane bottles bobbing in the dark, roiling water that raced past us, but never any hands summoning help.

In the morning, we found those hands. The bodies were stripped of clothing and covered with mud. The first I saw was of a woman who we guessed was 18, not much younger than I was then. This thin margin between life and death was startling in my young eyes.

Eventually, 144 people were declared victims of the flooding that night (although one turned up alive in 2008 in Oklahoma).

Estes Park got some rain, but not all that much. The larger story was partway down the canyon, in the Glen Haven and Glen Comfort areas, where the thunderstorm hovered. In just a few hours, it dropped 10 to 14 inches of water.

Downstream in the canyon, just above the Narrows, some people were unaware that anything was amiss until they went outside their houses and saw the water rising in their yards. It hadn’t even rained there. One cabin I saw a few days later was stripped of doors and windows but stood on its foundations, a mound of mud 5 or 6 feet high in the interior. I seem to recall a dog barking as we approached, protecting that small part of the familiar in a world gone mad.

At the old hydroelectric plant where my family had once enjoyed Sunday picnics, the brick building had vanished. Only the turbines and concrete foundation remained. In a nearby tree, amid the branches maybe 10 or 15 feet off the ground, hung a lifeless body.

The river that night carried 32,000 cubic feet per second of water at the mouth of the canyon, near where I was stationed. It happened almost instantaneously — and then it was gone. It was a flash flood.

#Runoff news: Northern #Colorado rivers have likely peaked for the season

From The Fort Collins Coloradoan (Jacy Marmaduke):

The Poudre and Big Thompson rivers are gushing as a wave of warm weather sends mountain snowmelt rushing toward Northern Colorado, but regional officials say flows should taper this week and don’t expect major flooding.

The Poudre flowed about 4.3 feet high at the Lincoln Street gauge Tuesday afternoon. Its volume of 956 cubic feet per second was nearly three times the median for this time of year…

A blast of summer heat will bring Fort Collins a string of days with highs above 90 degrees, starting Wednesday and holding on through Saturday, according to the National Weather Service. Hodges said flood risk isn’t a big concern, though, because so much of the mountain snowpack that feeds the Big Thompson and Poudre rivers has already melted…

Remaining snowpack is plummeting in both the North Platte and South Platte river basins, according to the Natural Resources Conservation Service…

The onset of summer also means people will divert more water from the Poudre, which loses over 60% of its water before it even gets to Fort Collins…

The Big Thompson and Poudre rivers have likely already reached their peaks, Hodges said. The Big Thompson reached about 5.8 feet — action stage for flooding is 6.5 — above the canyon mouth on Thursday, according to the Colorado Division of Water Resources…

The Poudre reached about 5.7 feet at the canyon mouth Friday. Action stage is 6.5 feet. It peaked at about 5.5 feet through town on Friday, well below the action stage of 9 feet.

From OutThereColorado.com (Spencer McKee):

The warmer temperatures in Colorado’s mountains are expected to melt quite a bit of snowpack. Be warned that Colorado’s rivers and waterways will be swollen with fast moving and powerful water, making them very dangerous. Three people have died in three separate incidents over the past week in Colorado rivers.

Larimer County is still waiting for $20 million from FEMA for repairs after 2013 floods

Damage to US 34 along the Big Thompson River September 2013. Photo credit: CDOT

From The Fort Collins Coloradoan (Jacy Marmaduke):

Nearly six years after the Big Thompson River flood wrecked U.S. Highway 34, stranded Estes Park and wiped out bridges and homes, the U.S. government has yet to fund $20 million of repairs in Larimer County.

The county hasn’t started construction on County Road 47 (Big Elk Meadows) and County Road 44H (Buckhorn) because of the lack of funding. The county finished work on Big Thompson River bridges destroyed and rebuilt after the flood but hasn’t been reimbursed by the Federal Emergency Management Agency for the project.

The delay in FEMA funding for Larimer County’s last three flood recovery projects has county officials in a bind: As another construction season looms without federal money, so does a crucial state deadline.

Colorado’s general fund has paid for about 13% of Larimer County’s flood restoration work since 2013. Come September 2020, state funding for the projects will dry up.

“We will not be able to meet that deadline with the delays we’ve had because of this issue,” said Lori Hodges, Larimer County emergency management director. “Our biggest projects are at risk because we haven’t gotten the guidance we need.”

The holdup is essentially a bureaucratic issue. Congress passed a law in October 2018 changing the way FEMA awards money for disaster recovery work.

FEMA used to deny funding for all projects that didn’t meet a strict set of code compliance guidelines. The guidelines had little wiggle room for projects on roads and bridges in complex terrain — like the ones destroyed by the flood in the Big Thompson canyon. For example, a road repair in a narrow, rocky canyon probably couldn’t meet FEMA’s requirement for shoulder width.

The Disaster Recovery Reform Act of 2018 instructed FEMA to award money for projects that don’t meet the strict guidelines as long as a local engineer signs off on the work and agrees a waiver is necessary. Congress gave FEMA 60 days to give its regional offices guidance on how to award funding under the new law.

But FEMA hasn’t done that yet, so regional officials won’t fund the implicated Larimer County projects, Hodges said. FEMA Region 8 spokesperson Lynn Kimbrough told the Coloradoan the office paused a Larimer County funding appeal as it waits for policy guidance from headquarters…

CR 47, partially destroyed by the flood, branches off U.S. Highway 36 between Lyons and Estes Park. The road is accessible but unpaved. An 11-mile stretch of CR 44H, located in Buckhorn Canyon and the Roosevelt National Forest, was heavily damaged in the flood and the High Park Fire in 2012.

#Snowpack/#Runoff news: @Northern_Water declares a 70% quota for the 2019 season #ColoradoRiver #COriver

Lake Granby spill June 2011 via USBR. Granby Dam was retrofitted with a hydroelectric component and began producing electricity earlier this year as water is released in the Colorado River.

From The Loveland Reporter-Herald (Sam Lounsberry):

Unit owners of the Colorado-Big Thompson project, which delivers Colorado River water from the wet Western Slope to the dryer Front Range, will get 70% of their quota this year, according to a Northern Water news release.

The 70% allocation means that a farmer who owns 10 acre-feet of Colorado-Big Thompson water will get seven in a year, with the remaining three kept in storage for use in dry years…

In wet years like this one, Northern sometimes downsizes the quota of Colorado-Big Thompson water distributed, since native streams can be full enough to provide farmers late-season growing supply, which provides Northern a storage opportunity for use in dry years.

But the move to boost the Colorado-Big Thompson quota from 50% — the level normally set at the start of Northern’s water year in November just to get users through the winter so snowfall can inform spring allocation rates — ensures farmers will have a more flexible late growing season.

The quota increases available Colorado-Big Thompson water supplies by 62,000 acre-feet from the initial 50% quota made available in November…

The snow-water equivalent mark for the Upper Colorado Basin is 120% of the normal median as of Thursday, according to the U.S. Bureau of Reclamation, with snowpack levels in other river basins across the southwest at even higher marks. But KUNC and The Aspen Times reported this year that despite the good snowfall this winter, officials predict spring runoff won’t be enough to replenish reservoirs across the southwest, because years of drought have left dry soil that sucks up extra drops.

“Modeled soil moisture conditions as of November 15th were below average over most of the Upper Colorado River Basin and Great Basin,” the Colorado Basin River Forecast Center stated in its April 1 report. “In the Upper Colorado River Mainstem River Basin, soil moisture conditions were below average in headwater basins along the Continental Divide, and closer to average downstream.”

Water from the Colorado-Big Thompson project supplements other sources for 33 cities and towns, 120 agricultural irrigation companies, various industries and other water users within Northern Water’s 1.6 million-acre service area, across parts of eight counties, the Northern release said.

Westwide SNOTEL basin-filled map April 11, 2019 via the NRCS.

Loveland: @Northern_Water Spring Water Users Meeting Tuesday, April 9, 2019

Click here to read the agenda.

Map of the Colorado-Big Thompson Project via Northern Water

Big Thompson Canyon construction named national “Best of the Best” — The Loveland Reporter-Herald

Damage to US 34 along the Big Thompson River September 2013. Photo credit: CDOT

From The Loveland Reporter-Herald (Pamela Johnson):

The reconstruction of U.S. 34 in the Big Thompson Canyon was chosen from 820 construction projects nationwide to be named Best of the Best by Engineering New Record.

Several partners in the project — Kiewit Construction, Colorado Department of Transportation, Jacobs, the engineering firm, and a handful of subcontractors — are named on the award that was presented Friday in New York City.

“You would not believe the projects it beat out — vertical construction, a new cadet building for the Army, other just very complicated projects,” said Doug Stremel, project manager with Jacobs.

“It’s really exciting … It was a collaborative effort for CDOT, Kiewit and Jacobs and the others. It was a team effort. We’re happy to share in it, but it really was a collaborative effort.”

Upper Thompson Sanitation District and the Town of Estes Park to turn dirt on sanitary sewer project

Estes Park

From The Estes Park Trail-Gazette (Tyler Pialet):

Through an Intergovernmental Agreement, the Upper Thompson Sanitation District (UTSD) and the Town of Estes Park (TEP) are partnering to complete a utility infrastructure project that will impact the Fish Creek Lift Station and Mall Road.

The work, which is expected to start on Jan. 28, will start with replacing a single, 45-year-old sanitary sewer force main with new, dual-force mains. These will extend from the Fish Creek Lift Station, located on Fish Creek Road next to Lake Estes, across U.S. 36 to UTSD’s gravity sewer main near Joel Estes Drive.

“UTSD recognized the lift station force main was a critical piece of infrastructure, had been in operation for 40 years, and due to its design features, had received minimal maintenance,” said UTSD District Manager Chris Bieker.

Bieker explained that force mains are pressurized sewer pipes that convey wastewater where gravity is not possible.

“Moving the flow uphill requires a pump,” he said. “Pumping facilities called lift stations may be required to transport the wastewater through the collection system.”

According to Bieker, “The Fish Creek Lift Station and approximately 1,000 linear feet of 14-inch diameter cast iron force main was constructed in the mid-1970s. The interior of the force main is cement mortar lined. Approximately 600 linear feet of force main is located south of Highway 36. The remaining 400 feet crosses north underneath HWY 36 and discharges to a manhole located in Mall Road. Wastewater then flows along Mall Road through approximately 1200 linear feet of gravity sewer main to the treatment facility…

In late 2016, the District televised the interior of the force main. The video indicated cracking and delamination of the cement mortar pipe lining within sections of the force main. The televising operation prematurely ceased when the camera could not proceed any further due to the internal conditions of the pipe.”

New piping and valves will be added to the Fish Creek Lift Station. Old, aging pipes and valves will be replaced to facilitate new parallel force mains. As the Fish Creek Lift Station manages over a third of all of the district’s water flows, these improvements are critical to UTSD operations and public health.