#Runoff/#Snowpack news: Dolores is sizing up snowmelt flooding potential

Dolores

From The Cortez Journal (Jim Mimiaga):

On Monday, 30 officials and residents attended an informational meeting at the Dolores Fire Station hosted by Montezuma County emergency manager Mike Pasquin.

The town has not experienced a major flood from the river since 1911, which filled the town valley with up to 3 feet of water.

But there is potential this year because of the heavy snowpack, warming weather, and wet El Niño weather pattern.

The Dolores River peaks from snowmelt between May 15 and June 15, officials said. How much comes down and at what rate depends on snowpack levels, temperature, rain and soil moisture. Runoff forecasting is an educated guess, and possible flood levels require ground truthing as well.

There are some trigger points to watch for, officials said.

Flood stage for the Dolores River in town is 8 feet. A safe maximum flow of the Dolores River is about 6,000 cubic feet per second in town, said Ken Curtis of the Dolores Water Conservancy District.

Flows above that increases the risk of flooding, and flows of 7,000 or 8,000 cfs would start to overflow the banks. Flows can be viewed by visiting the Dolores River Boating Advocates web page

Increased flows from a hot spell or rain event in the upper valley takes time to reach town and usually arrives at night, said town board member Val Truelsen, “so there should be some nighttime monitoring of the banks.”

Residents should stay tuned to the National Weather Service for regional and local flood watches and warnings.

Montezuma County Sheriff Steve Nowlin said the community will be given warnings about predicted flooding conditions through media outlets, town reports, reverse 911, Nixle and social media. The town has recently repaired emergency siren that would also be activated as a warning.

Bridges up the valley are being monitored for debris accumulation and to ensure boaters can safely get under them. Collapsed mines in Rico that collect runoff have automated sensors that warn emergency personnel if the pressure and levels are too high, triggering relief valves.

Community sandbagging projects are happening in some flood-prone towns in the state, said Karen Dixon, emergency manager for the county health department. Local agencies said they are ready to respond to a flood emergency with equipment and staff.

If needed, sand is available at the county shop on County Road 30, said county road manager Rob Englehart.

Officials said severe flooding could compromise utility systems such as water, sewer and natural gas lines, and cause them to be shut down until the water recedes and repairs are made.

Potential shelter areas for evacuees discussed were the Dolores Community Center, Dolores High School, county fairgrounds, House Creek and McPhee campgrounds, and Canyons of the Ancients Museum and Visitor’s Center.

Westwide SNOTEL basin-filled map April 16, 2019 via the NRCS.

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.”

USACE Omaha District: Corps provides updates on current levee breaches and damage assessments #Flood2019

Here’s the release from the U.S. Army Corps of Engineers, Omaha District (Capt. Ryan Hignight):

The U.S. Army Corps of Engineers, Omaha District continues to work with state, local, and tribal governments to repair damaged levees from the 2019 unregulated runoff event. There are over 350 miles of levees on the Missouri, Platte and Elkhorn rivers and tributaries that have experienced significant flood damage. Due to the magnitude of damage along these levees, repair efforts will take an extended period of time. The Omaha District is initiating efforts to perform damage assessments as water recedes and access to the levee system becomes available.

Omaha District Commander Col. John Hudson visited Pierre, South Dakota and met with state emergency management officials. They discussed flood forecasts as well as Omaha District’s ability to respond to state, county, or tribal requests for assistance. Col. Hudson also met with South Dakota Governor Kristi Noem and Congressman Dusty Johnson. Col Hudson provided them with a situational update on Omaha District’s capabilities regarding the upcoming spring thaw and potential rains. He also discussed the Army Corps’ technical assistance in Sioux Falls, South Dakota concerning high flows and snow melt concerns.

The District is sending notification to levee sponsors in the PL 84-99 program on Monday, March 25 with information on how to request damage assessment and levee repairs. Levees must be active in the Public Law 84-99 program to be eligible for repairs.

Much of the levee system remains compromised due to the record inflows surpassing their designed protection levels.

As of noon today, there were 47 confirmed breaches at L611-614 (South of Council Bluffs, Iowa), L-601 (South of Glenwood, Iowa), L-594 (near Fremont County, Iowa), L-575 (Fremont County, Iowa), L-550 (Atchison County, Missouri), L-536 (Atchinson County, Missouri), R-613 (Sarpy County, Nebraska), R-562 (Nemaha County, Nebraska), Western Sarpy (Ashland, Nebraska), Clear Creek (Ashland, Nebraska), Union Levee (Valley, Nebraska), and R-573 (Otoe County, Nebraska). In addition, levee 550 remains overtopping.

The Omaha District is initiating efforts to perform damage assessments as the water recedes and access to the levee systems becomes available. The District has already begun initiating underwater surveys of scour holes along the Missouri and Platte rivers as well as collecting aerial imagery to support these efforts.

Omaha District’s focus remains on ensuring the safety of citizens and communicating the conditions on the river systems to all of our partners and stakeholders. The Corps continues to provide flood fight assistance to state, local, and tribal government agencies.

The Omaha District has distributed approximately 227,000 sandbags, 2,020 super sandbags, 9,930 feet of HESCO barriers, seven pumps and 21 poly rolls.

The first source of information for citizens is their local emergency managers. For questions or concerns you can call 211, which is a national resource hotline and website geared to local area needs.

11-foot wall of water: One dam breaks, three counties suffer — The Lincoln Journal Star

Nebraska state officials flew over the flood-ravaged Spencer Dam on March 16, 2019. The Niobrara River had been running at 5 or 6 feet of gage height before it broke through the 90-year-old dam early on March 14, 2019. After that, an 11-foot wave rolled through. Photo credit: State of Nebraska

Here’s a report on the flooding in Nebraska from Peter Salter writing for The Lincoln Journal Star. Click through and read the whole article and check out the various videos. Here’s an excerpt:

From their offices in Lincoln early Thursday, hydrologists with the U.S. Geological Survey were monitoring the final few moments of a stream gauge more than 200 miles away, on the Niobrara River.

It was hinting at something catastrophic.

“We were watching it from here, and it looked like something incredible was happening that we couldn’t believe,” said Jason Lambrecht. “And suddenly, everything went dark.”

The gauge had been ripped away by the wall of water released when the 90-year-old Spencer Dam failed under the pressure of the river, swollen with rain and rapid snowmelt and broken ice. But its last readings allowed Lambrecht to measure the size of the surge.

Earlier, the Niobrara had been running at 5 or 6 feet of gauge height. After it broke through the dam, it measured nearly 17.5 feet. It wasn’t a gradual increase, either…

And in its wake, three Nebraska counties would learn how that much moving water can become immediately destructive and potentially deadly. How it can cause instant pain and long-term suffering. How it can harm not only those in its path, but those living miles away.

First, the wave swept away a section of U.S. 281, a nearby riverside saloon and at least one home, possibly occupied. And it continued downstream, barreling toward the town of Niobrara — and its mouth at the Missouri River — about 40 miles away.

Knox County: ‘It’s crazy’

The service station owners thought they were ready for the coming water.

They’d taken the tire machine and other equipment away. They brought the important paperwork home. They put their ’68 Camaro up on the lift. They moved the rest of what they could to higher ground, filling the rafters with inventory.

And the couple had a huge inventory. Vic’s Service has anchored the west edge of Niobrara for 25 years, and had enough hydraulic fittings and plumbing pieces to serve as a kind of farmer’s supply store, said Ruth Janak, who co-owns the station with her husband, Victor.

They checked on their business Wednesday, and found it already swamped with 4 feet of water, her desk upturned, pop machines on their sides. A mess, but nothing they couldn’t handle.

“We thought, when the water recedes, we’ll be able to get in and clean all that up,” she said.

They returned Thursday, and found most of it missing.

“Our main building, the one we did our business at, it’s gone. The gas pumps are gone. We lost the propane tank. So many tools are gone,” Janak said Friday. “Where’s all that stuff at? It’s crazy.”

Later, she would find a jug of hydraulic fluid — and someone else’s pontoon boat — on what remained of the town’s golf course. But their main building, and much of what it contained, had likely tumbled downstream.

Theirs wasn’t the only missing building. The wall of water had brutalized Niobrara’s west side, a low-lying commercial district, and the part of town closest to the river.

Jody Stark, the chair of the village board, listed the other casualties. Several buildings from a hay business? Gone. A state Department of Transportation garage? Gone. A Knox County road shop? Gone. The Mormon Bridge on Nebraska 12? Stark has video of the deck floating away. The Country Cafe? Still standing, but it had been nearly swallowed by water and ice, with maybe a foot of the roof visible at one point.

“A lot of buildings washed away,” he said. “They were pretty much swept right down the river and they’re in the Missouri somewhere.”

The good news? Almost all of the 300 or so residents of Niobrara live on higher ground, and weren’t directly hurt by the floodwaters…

Still, his town was struggling. The flooding compromised the town’s two wells, leaving its residents without a water supply, and the fire department was going door-to-door, filling containers. Getting in and out of town was also difficult; by Friday, the Standing Bear Bridge to South Dakota had reopened, and there was one passable gravel road south of town. Nebraska 14, the main route south out of Niobrara, was so strewn with ice it was only open for emergency travel.

The damage was unprecedented, Stark said, and worse than they had originally expected. But that was before they’d heard the Spencer Dam had failed and even more water was headed their way…

The Spencer Dam was a flow-through hydroelectric dam, with garage-type doors that let water through, and Becker said it wasn’t known whether the doors had been open or closed at the time. They disappeared downstream, he said.

Its breach triggered immediate and long-term problems. It swept away a Holt County house just downstream, and authorities were still searching for its owner.

“On March 14th at around 5 in the morning the dam on the niobrara river south of Spencer NE was overtaken by flooding and ice jams. 2 days prior to this there was significant snow melting. 1 day prior there was all day rain measuring 1-1.5 inches. The ground was still frozen from recent below normal temperatures. All that water broke loose ice chunks the size of cars and trucks. The dam was no match for this extreme force. The dam and the dike were both destroyed. The water then washed out Hwy 281 and flooding many communities downstream.” — Birkel Dirtwork

And the force of the flow severed the supply of water to the north, in Boyd County. Many of its 2,000 residents relied on the pipeline from Holt County that was buried beneath the river. Now that it’s gone, they don’t have the water they need for drinking, for livestock, for flushing.

They received a truckload of bottled water Friday, enough to last maybe a day, said Doug Fox, Boyd County’s emergency management coordinator. They need more…

And Boyd County was struggling to stay connected with the rest of the state. The failure of Spencer Dam took out a pair of routes over the Niobrara River, and the only ways out of Boyd County were north into South Dakota or west into Keya Paha County, Fox said.

Nebraska Rivers Shown on the Map: Beaver Creek, Big Blue River, Calamus River, Dismal River, Elkhorn River, Frenchman Creek, Little Blue River, Lodgepole Creek, Logan Creek, Loup River, Medicine Creek, Middle Loup River, Missouri River, Niobrara River, North Fork Big Nemaha River, North Loup River, North Platte River, Platte River, Republican River, Shell Creek, South Loup River, South Platte River, White River and Wood River. Nebraska Lakes Shown on the Map: Harlan County Lake, Hugh Butler Lake, Lake McConaughy, Lewis and Clark Lake and Merritt Reservoir. Map credit: Geology.com

Judge Matsch pauses #ColoradoSprings #stormwater lawsuit until April 12, 2019

Colorado Springs with the Front Range in background. Photo credit Wikipedia.

From The Colorado Springs Gazette (Conrad Swanson):

Colorado Springs and the four parties suing the city now have an extra month to either settle a longstanding lawsuit over federal stormwater permit violations or agree how to continue the case in court.

U.S. District Judge Richard P. Matsch in December ordered the case paused until this month so the parties could find common ground. The lawsuit was to restart last week, but Matsch extended the break by more than a month.

Now the parties have until April 12 to agree on next steps, or the case goes back to court.

The request for a break in the case came from the plaintiffs — the U.S. Environmental Protection Agency, the Colorado Department of Public Health and Environment, Pueblo County and the Lower Arkansas Valley Water Conservancy District — after Matsch ruled that Colorado Springs violated federal stormwater regulations at three development sites.

The March 2019 @CWCB_DNR “Floodstage” newsletter is hot off the presses

Cherry Creek Flood August 3, 1933 — photo via the Denver Public Library

Click here to read the newsletter. Here’s an excerpt:

As of mid-February, Colorado’s statewide snowpack sat at 108% of normal. Snowpack is higher in the northern and eastern basins and lower in the southwestern basins. The climate forecasts through the runoff season suggest that these numbers could climb higher as fore- casts indicate a wet spring statewide.

Higher snowpack percentages can increase the possibility of snow- melt flooding. Generally, watersheds are monitored for this once they reach 130% snowpack. Currently, no watersheds exceed this threshold, but state officials continue to monitor conditions due to the wet climate forecast moving forward. To view snowpack conditions and better understand the potential flood threat in your location, visit the Natural Resources Conservation Service’s Snow Telemetry (SNOTEL) and Snow Course Data and Products page.

It is worth mentioning that, as indicated by looking back through Colorado’s history, the majority of flooding events occurring through- out the state are rain-based and not snowmelt-based. In fact, the last year of widespread snowmelt flooding was in 1984, although isolated instances have occurred since then. One area of ongoing concern relates to rain-on-snow events, in which high elevation, late spring rainstorms fall on still surviving snowfields. This can quickly exacerbate runoff and create problems that wouldn’t exist in the absence of either the rain or the snow.

#AnimasRiver: @EPA to use “adaptive management” strategy for Bonita Peak Superfund site

On April 7, 2016, the Environmental Protection Agency proposed adding the “Bonita Peak Mining District” to the National Priorities List, making it eligible for Superfund. Forty-eight mine portals and tailings piles are “under consideration” to be included. The Gold King Mine will almost certainly be on the final list, as will the nearby American Tunnel. The Mayflower Mill #4 tailings repository, just outside Silverton, is another likely candidate, given that it appears to be leaching large quantities of metals into the Animas River. What Superfund will entail for the area beyond that, and when the actual cleanup will begin, remains unclear.
Eric Baker

From The Durango Herald (Jonathan Romeo):

The Bonita Peak Mining District Superfund site, which includes 48 mining-related sites around Silverton, is one of six Superfunds nationwide to be part of the study, referred to as an “adaptive management” strategy.

“We are really excited about this for Bonita Peak,” said Christina Progess, Superfund remedial project manager.

In May 2017, then-EPA administrator Scott Pruitt formed a task force to think about ways to speed up Superfund cleanups, which in some cases can take decades to complete.

A month later, the task force recommended an “adaptive management” strategy that would improve and accelerate the process. Government agencies have used adaptive management since at least the 1970s, but the task force’s move made it formal for EPA.

Kate Garufi, an environmental engineer for EPA who is also chairwoman of the adaptive management task work force, said that some Superfund sites are large and complex, and it can take years to formulate a long-term cleanup plan.

“When you look at Superfund, it’s historically been very linear with a site investigation, evaluating alternatives, selecting a decision and implementing it, which can take a very long time,” she said.

Adaptive management, however, allows the EPA to target quicker projects year to year while a comprehensive solution is investigated, Garufi said.

“We’ll be able to take early actions and see those benefits while we continue to evaluate the entire basin,” she said.

The strategy made perfect sense for Bonita Peak, Progess said, which at 48 individual mining sites across the entire headwaters of the Animas River Basin is one of the larger and more complicated Superfund sites in the country.

As part of the adaptive management, Bonita Peak will be part of the 12-month study, which will set various goals and engage the local community.

“Because we are so early in the investigative process at Bonita Peak, adaptive management will help us set those goals and how to achieve them,” Progess said…

In June 2018, the EPA released a “quick action” plan for cleanup work at 26 mining sites over the next five years to be conducted while the agency comes up with a more long-term, comprehensive strategy to address mine pollution around Silverton.

The plan met resistance from local groups and individuals who say the plan fails to first quantify the benefits and goals that would result from the action plan, which would cost millions of dollars to clean up sites considered smaller contributors of pollution.

Thomas said the adaptive management will help refine that plan. She said a final decision, called an interim Record of Decision, could be issued within the next month or so.

On Wednesday, Thomas also addressed the concern that the partial government shutdown, which lasted 35 days, would cause the EPA to lose a summer season’s worth of work at Bonita Peak.

“Of course everyone here at EPA was dismayed about government shutdown, and it’s good to get back to work,” Thomas said. “Clearly there have been some impacts to the work we were all doing, but we’re doing our best to make sure we can take advantage of a full summer season.”