From The Greeley Tribune (Trevor Reid):

Using dynamic forecasting models, climate scientists like Andreas Prein are looking at how intense rainstorms are changing over the coming decades.

Prein, a climate modeling scientist at the National Center for Atmospheric Research in Boulder, said warmer climates are leading to more frequent heavy rainfalls. Since 1950, the number of three-inch rainfalls in a day has increased about 25 percent across the U.S., according to Chad Gimmestad, senior forecaster for the National Weather Service Office in Boulder. Prein explained that the warmer air holds more moisture, so when rain falls more water is dumped than normal in cooler conditions.

“We have stronger evaporation over the ocean because it’s warmer, and then this moisture is transported over the continent,” Prein said. “It is basically exactly what happened in 2013 during the Colorado flood.”

Looking at the regional trends, Gimmestad said the heaviest two rainfalls expected in a year have increased about 10 to 20 percent in the western U.S. In Colorado, where there were once a two-and-a-quarter inch rainfalls, forecasters see two-and-a-half inch rainfalls, he said. While that increase isn’t as large as it is in the eastern U.S., where the heaviest rainfalls in a year have increased from 30 to 60 percent, it still has a significant effect.

“That’s when your flood occurs, so you just made your flood 10 percent bigger,” Gimmestad said..

Prein said the Front Range’s major flood events are often related to a stream of moisture from the Gulf of Mexico from the south traveling north along the mountains and turning west to create upslope flows. As the mountains push the moist air upwards, the heavy rainfalls are practically anchored by the mountains. Gimmestad, who commuted from Greeley to Boulder during the floods, said forecasters knew something big could happen from the weather patterns in 2013, but seeing it was something else. Gimmestad drove to Boulder on the night of Sept. 12, the second night of the heaviest rain during the flood. After about three hours of driving around, he found the one bridge still above the water over Boulder Creek. By the time he drove back to Greeley the morning of Sept. 13, he had to go out to Kersey because everything upstream on the Platte had flooded…

Laura Read, a water resources engineer at the National Center for Atmospheric Research, said the heavy rainfalls led to sustained flooding because of the Front Range’s relatively flat topography next to the steep gradient of the foothills. Residents in areas like Milliken didn’t see the flooding go down for as long as two weeks because the flood brought the groundwater table up, she explained. As the water came up from the ground from the 2013 flood, it caused additional damages to structures…

Brad Udall, senior water and climate research scientist at Colorado State University’s Colorado Water Institute, said scientists of just a few years ago were asking the wrong question about climate change’s effect on extreme weather events. Where scientists before framed the conversation about whether or not climate change caused extreme weather, they’re now looking at how it impacts these cyclical events.

“Climate change may not have caused them, but they add to their intensity. It adds to their frequency. It can add to their duration,” Udall said.

Scientists are still hashing out the degree to which climate change impacted the 2013 flood, Udall said. Heavier rainfalls, drier soils and growing risk for wildfires — which leads to more erosion, Read explained — are expected with the warming climates, experts said. Though there’s not yet enough data to definitively say whether these conditions will lead to more events like the 2013 flood, Udall said climate change is creating unprecedented weather events.

“We’re now in an era, because of climate change, where all the sudden our predictability has gone away,” he said. “We need to be prepared for really bad outcomes.”

From The Fort Collins Coloradoan (Holly Engelman):

The fast-moving water as a result of a storm system stalled over the Front Range inundated parts of Loveland, Lyons, Greeley and Boulder. Fort Collins saw little damage, though the flood temporarily impacted the ability to get in and out of the city.

Nine deaths were attributed to the flooding — two in Larimer County — and an estimated 2,000 homes were damaged or destroyed statewide, according to a Coloradoan report at the one-year anniversary of the flood. Parts of U.S. Highway 34 and other roadways were washed away.

The September 2013 flood ranks among the worst natural disasters in Colorado history, according to reporting during that time. The flood changed the landscape of Northern Colorado and led to years of rebuilding, including projects that just wrapped up this year.

Here’s a photo gallery from The Fort Collins Coloradoan.

From The Loveland Reporter-Herald (Hans Peter):

With every flood, Loveland gets a little wiser.

The evidence can be seen in a new network of water gauges, a bolstered mass-notification system, and in the memories of residents five years after the 2013 flood rushed into Loveland. The wisdom will be useful if — more likely, when — another flood takes place in Larimer County.

“Floods are part of life here,” said Loveland Fire Rescue Authority Capt. Pat Mialy as she sat down with a 3-inch-thick binder titled “Flood Master Plan.” “Loveland is built at the bottom of a canyon; some things we can do nothing about, but we can help people become more prepared.”

Mialy, who is also Loveland’s emergency manager, said the city has an integral part in the Flood Master Plan, which encompasses the Big Thompson’s entire path through Larimer County, not just the flow at the mouth of the canyon.

Watching water

Mialy said zooming out and viewing Loveland as a part of other communities marks one of the key differences between the 2013 flood and the next inevitable flood. After all, storms don’t care about ZIP codes.

“We’re listening to Estes Park, we’re listening to Glen Haven,” Mialy said, alluding to a network between agencies that have strengthened ties since 2013. “All our flood systems were integrated; they all speak to each other.”

A network of gauges and number crunchers watches over Loveland and other Larimer communities. The county’s floodplain administrator, Eric Tracy, said if there’s heavy water upstream, he knows about it.

Tracy told the Reporter-Herald that in the 2013 flood, waters washed away the only U.S. Geological Survey water level gauge monitoring flow through the Big Thompson Canyon, and with it, any doubts that the county needed better ways to watch the water.

“It was a very reactive approach before 2013,” Tracy said, motioning toward a pole-mounted camera at the U.S. 34 bridge near Sleepy Hollow Camp. He said the Colorado Department of Transportation uses it to get video footage of the bridge, but that means almost no upstream warning when a flood might overtake the road or worse, wash it away.

Tracy said that, ironically, he and many other flood plain administrators were in Steamboat Springs for a convention the day the 2013 flood ripped through Larimer County. He rushed back as fast as he could to handle the damage…

“The next six months were a nightmare,” Tracy said, noting that his cellphone was a nonstop stream of emergency notifications at that time.

Now, his cellphone still gives him notifications as water moves around the canyon, but he gets them hours before a flood event, when preventative measures can be ordered. Different monitoring locations are programmed with low-, medium- and high-priority warnings that all reach Tracy’s phone, as well as many other devices.

That’s because today, the bridge over Sleepy Hollow, among other locations, has some new gadgets.

“It’s a tipping cup,” Tracy said, now pointing to the top of a metal pole in the ground. He explained that the cup acts as a rain gauge: when it fills up to a certain amount, it tips over. It then counts the number of tips over time and transmits that data back to the county.

Also new is a water pressure transducer, which measures the depth of the water based on the pressure.

Another gadget, mounted on the side of the bridge, bounces sonar off the surface of the river to measure real-time water levels, Tracy said. Best of all, that sonar detector won’t wash away unless the bridge does.

The measurements mean numbers, and those numbers — in the hands of civil engineers such as Tracy — mean real-world information. Combining the data with a geomorphic map of the flood plain, and the county can figure out when and where flooding will occur.

Now, new rain and water flow gauges have been placed at several places in upstream Larimer. According to Tracy, water gauges exist at Sleepy Hollow Camp, Olympus Dam, Mary’s Lake Road, Fall River, Devil’s Gulch, Glen Haven and Drake, among others in rural water flow areas.

“The data will help the National Weather Service ground truth on what they see on their radar systems and will assist in the accurate execution of weather alerts for the Big Thompson basin,” Tracy said. ” The data will also be used in real time in the Emergency Operations Center for large flood events to assist emergency personnel and road and bridge crews in the field.”

Mialy said Loveland authorities are privy to the same information, and they can view it on a dashboard with other agencies.

“We’re downstream,” Mialy said. “We will know what’s coming our way.”

Drop of prevention, gallon of cure

Lori Hodges, director of Larimer County’s Office of Emergency Management, said the 2013 flood marked a large shift in the county’s emergency preparedness — it also marked a change in her career.

“What’s new since 2013?” Hodges reflected, “Well, my office didn’t exist in 2013. … I was hired because of the flood.”

Hodges said that day one on the job, she updated the county flood plan to reflect the Larimer County Sheriff’s Office’s request for a broader plans, both geographically and socially.

“Before it was a response-based program,” Hodges told the Reporter-Herald. “They needed to look more broadly at mitigation.”

Part of that mitigation means preparing the public for an emergency flood and keeping them away from danger areas.

Sometimes, preparedness is as simple as knowing your neighbors, Hodges said. In the wake of both the 2013 flood and the 2012 High Park Wildfire, both of which called for federal emergency aid, Larimer County created Larimer Connects, a program designed to bridge gaps between county residents.

According to the program’s website, Larimer County has had the most federally declared disasters in Colorado; the website goes on to say that with a track record like that, it’s necessary for Coloradans to expect the worst, especially in unincorporated areas such as Glen Haven and Red Feather Lakes, both of which have created emergency plans since previous disasters.

Larimer Connects offers assistance in creating community hubs such as the North 40 Mountain Alliance, a self-sustaining nonprofit group surrounding Red Feather Lakes.

“The one thing we really did learn from the flood is that when communities are more connected, the better they do when there was a flood,” Hodges said. “It’s social capital; that will cause people to recover faster and better.”

Larimer Connects intends to build resilience within communities by connecting them to resources and each other.

Hodges said that ironically, densely populated areas such as Loveland and Fort Collins have less social capital; neighbors aren’t as tight or reliant on one another, meaning disasters can cause even more disruption.

Everbridge over troubled waters

Mialy said agencies within the county have no problem notifying one another of impending floods — thanks to the new data network — but that’s not enough: Residents must also be aware.

Since the 2013 flood, Loveland has urged residents to sign up for the Larimer Emergency Telephone Authority LETA911 emergency notification system that alerts residents of oncoming or current dangers.

Mialy said the system works almost exactly like an Amber Alert, which automatically notifies all cellphones in a given area of an abduction or other threat.

The problem is, Larimer County doesn’t have the authority to push notifications unless residents sign up.

When signed up, the system uses Everbridge, a mass-notification system to show road closures, evacuation notices and other warnings to all registered devices.

Loveland Fire Rescue Authority emergency management specialist Lenny Layman said through that system, authorities can type a message and draw a polygon on a digital map. When they say “go,” that message is delivered to any and all devices set up within that polygon.

With this system, law enforcement or emergency responders notify the public of an incident before residents feel the need to call dispatch.

He said this could prove especially useful in the event of a flood, when authorities can figure out exactly which neighborhoods could end up underwater.

Users can set up for notifications at multiple addresses. For instance, parents can add their child’s school to the list so they can receive notifications even if they aren’t near an affected area.

Moreover, LETA911 can ping a multitude of channels, including email, landlines, pagers and cellphones using both calls and texts.

“The more information we can send, faster, the more lives saved,” Leyman said. “But you have to opt into Everbridge.”

Mialy said that in her eyes, Loveland has only become stronger since 2013, despite the fact that the city remains in disaster recovery mode.

“We can’t prevent natural disasters,” Mialy said. “But we can identify all our weaknesses.”

Here’s an article with reactions to the flooding from The Greeley Tribune (Terry Frei).

From The Greeley Tribune (Joe Moylan):

In the weeks leading up to September 2013, the Weld County Sheriff’s Office was in the midst of emergency preparedness training.

In a sense, they were ready when a slow-moving cold front stalled over Colorado on Sept. 9, dropping several inches of rain. By the 15th, there was widespread flooding across a 200-mile stretch of the Front Range, including as far south as Colorado Springs and as far north as Fort Collins. A state of emergency was declared in 14 counties, including Weld.

Although deputies were fresh off emergency preparedness training, Weld County Sheriff Steve Reams said the floods identified critical deficiencies in the county’s infrastructure, namely communications.

“That’s something you don’t see everyday,” Reams said. “You don’t think about potential communications problems when you’re working a normal day in law enforcement.”

Colorado’s shared statewide communications system for emergency responders, pushed for in the wake of the 1999 Columbine High School shooting and again following 9/11, was the first to go, Reams said. It became overloaded and essentially worthless as flooding affected Boulder County, then all of Larimer County and finally all of Weld County.

When deputies abandoned the statewide system, they moved to cell phones, their secondary mode of communication, Reams said. But callers from throughout the country trying to check in on loved ones clogged the towers. As a last resort, the sheriff’s office orchestrated a lot of its moves by text message.

“Obviously that’s not the best way to conduct business,” Reams said. “The county has since created its own radio infrastructure that allows us to operate on our own platform. The bandwidth in the county has never been better.”

In addition to coordinating emergency response, Reams said the department had issues connecting with off-duty deputies to get them to come into work. Each deputy now has their own county-issued cell phone, so they can be reached in a timely manner in the event of an emergency. The department has also established better employee tracking to know who is available, even officers who are off-duty.

“Everything came down to an ability to communicate,” Reams said. “Once one mode went down, we had to find another mode of communication. Then that went down.

“You can fix almost any problem as long as you have the ability to communicate about it.”

If communications issues weren’t enough, the 2013 floods also illustrated the sheriff’s office error in keeping almost all of its emergency equipment centralized in Greeley. As the South Platte River breached its banks, it damaged 122 bridges and more than 650 lane-miles of road.

“Every major north-south road with a river crossing was completely wiped out,” Reams said. “Balancing equipment needs was a huge challenge as trying to get equipment from the north part of the county to the south was impossible.”

The Sheriff’s Office has since made changes to where it stages emergency equipment throughout the county.

In the city things weren’t quite as chaotic, said Pete Morgan, current Greeley Fire Marshal and the city’s emergency manager at the time of the flood. Fortunately, Greeley had beefed up its public safety communications prior to the flood, including working with cellphone providers to establish priority access to its networks in the event of an emergency. The city has since increased the number of employees across a variety of departments who have priority access to those networks.

But Morgan said the floods did show the fire department’s Water Rescue Team, trained in underwater rescue operations, was not prepared for swift water rescue needs as a result of the flooding.

The department has since gone from zero swift water rescue technicians to 15, with another five set to get their certification in the next year. Every Greeley fire employee with a response job at least has their swift water operations certificate, which is one rung below a swift water rescue technician, Morgan said. The department also has two swift water rescue instructors to perform in-house certification training.

Every fire truck and ladder now carries equipment specific to swift water rescue.

“The benefit with the additional equipment and certifications is when a swift water call comes in, we don’t have to wait for the Water Rescue Team to gear up and come out to the scene,” Morgan said. “We can respond directly with any of our trucks and ladders to begin rescue measures.”

The city also created an Incident Response Team composed of Greeley’s police, fire, public works, water & sewer, public information, risk management, and information technology departments, among others. Representatives from each department meet and train regularly about how to coordinate response efforts.