BISMARCK – Count John and Susan Boyce among the many who now know firsthand that the Missouri River can humble even the gigantic Garrison Dam.
Their home, in the leafy Sandy River Drive neighborhood north of Bismarck, is normally a couple of hundred yards from the Missouri River.
The ranch-style house was built in what was considered the 500-year floodplain, thanks to Garrison Dam, an earthen flood-control fortress 70 miles upstream. For almost 60 years, the dam kept areas like Sandy River Drive and numerous towns and subdivisions, as well as farms and ranches, dry during floods.
For the Boyces, that changed on June 2, 2011, when a dike breached and half a foot of floodwater inundated their home.
“I guess this is one in 500,” Susan Boyce, 60, said. “We never, ever imagined that this would happen.”
Just the day before, for the first time in history, the emergency spillway gates of Garrison Dam were opened for operation.
The historic flood of 2011 had begun. It was the first significant flood Bismarck-Mandan experienced since 1952. Yet without Garrison and the other dams, the record flooding and resulting damage would have been much, much worse.
Uncontrolled, the Missouri River flood crest in Bismarck-Mandan would have been more than 5 feet higher than it was – 24.43 feet instead of 19.23 feet, according to calculations by the U.S. Army Corps of Engineers.
The cumulative volume of water in the 2011 flood was almost 1½ times greater than the 1952 flood, which had the highest peak volume. The crest of the 1952 flood was more than 8 feet higher than 2011, 27.9 feet compared to 19.23 feet, because the dam spread the releases over a longer period.
In the 1960s, once the six Missouri River dams were in place and operating, officials spoke proudly of taming the mighty Missouri River, which used to flood with aggravating frequency.
Over time, as the dams withstood whatever nature threw their way, public confidence in their floodprotection reliability only grew.
The Boyces were far from alone in believing Garrison Dam would protect their property against any conceivable flood.
Todd Sando, North Dakota’s state engineer, for instance, was among the many who had faith in the Missouri River dams.
“I thought we solved our flooding,” he said. “We had no variability in river flow, really. The dams protected us.”
In retrospect, a flood caused by an ice jam that flooded low-lying areas around south Bismarck in 2009 was a warning. But that flood was minor and lasted only hours.
The 2011 flood lasted a bit more than three months.
Freakish weather, producing the highest runoff on record, was to blame.
Heavy snowpack in the Rocky Mountains, which drain into the Missouri, was followed by monsoon rains over a vast area of eastern Montana and the western Dakotas.
“It’s just the magnitude of the runoff,” Sando said. “The system wasn’t designed to handle it. This flood is so epic.”
Chased from their home by the flood, the Boyces have been living in a condominium in Bismarck. They are among an estimated 1,600 people in 700 residences displaced by the historic 2011 flood in Burleigh County.
Across the river in Morton County, more than 130 residences were damaged and about 760 people were evacuated – figures that merely hint at the flood’s human toll.
Evacuees scattered to rentals, were taken in by friends or relatives, or camped out in recreational vehicles.
Most residences were damaged by high ground water tables. The high pressure buckled basement walls, or the sheer volume of water overwhelmed sump pumps.
As it turned out, the flood crested almost 1½ feet short of the prediction, sparing many properties from even worse damage.
Early estimates by state officials put damage from the 2011 Missouri River flood at $35 million, a fraction of the $509 million statewide total.
“I think it could have been much worse,” said Cecily Fong, a spokeswoman for the North Dakota Department of Emergency Services.
The Boyces are among those who consider themselves fortunate the damage wasn’t more severe. Still, they had to gut the interior of their house, filling more than four rollaway disposals with ruined drywall, carpeting and belongings.
“My whole house is just one big mold pit,” said Susan Boyce, who teaches art in Mandan. “All our books are ruined.”
In the scramble to prepare for the flood, the Boyces weren’t able to move their piano. The best they could do was cover it, put it up on blocks and hope the water didn’t reach it.
The prolonged flood didn’t allow them to even examine their cherished piano until late summer.
When the couple unwrapped it, they were pleased to see that it didn’t appear damaged. But the real test would be how it sounded.
The Boyces braced themselves, then John, 60, a veterinarian, played the first chord. It sounded surprisingly good.
“We both started crying,” Susan Boyce said. “Sounds wonderful and looks wonderful and seems to be fine.”
The first alarms of a possible severe spring flood on the upper Missouri River were sounded in late January.
An engineer for the Burleigh County Water Resource District sent an email telling the Army Corps of Engineers that the public was “a bit jumpy,” and spoke of the need to “get rid of water.”
The basin’s January runoff was 170 percent of normal, with precipitation running 175 percent of normal. The National Weather Service described water stored in the snowpack as “near historic highs.” Much of the basin was saturated.
In February, Jody Farhat, who manages the Missouri River dam system, was aware that Bismarck lacked river channel capacity. She warned fellow corps officials that managing the spring runoff would be “a tricky operation.”
Meanwhile, nature kept piling up the warning signs – abnormally high snowpack and high snow water equivalents across much of the basin.
Still, in March, Farhat was saying the reservoir system still had plenty of room, if needed, to store floodwaters.
By late March, the corps was projecting releases from the Missouri River dams to reflect “slightly above normal to above normal” runoff.
Soon, however, it would be clear that spring runoff from the mountains and plains would be well above normal.
The corps began increasing dam releases in early April to make room for heavy runoff. Internally, according to emails that since have been made public, some corps officials wondered if Farhat wasn’t downplaying the chance of heavy rain.
In mid-April, a corps general sent out a mass email from headquarters warning that all the ingredients were in place for major flooding.
Sando wrote a letter dated April 20 to express concerns to the corps that its reservoir discharges seemed inadequate for the snowpack and possibility of heavy rain.
Those worries proved prophetic.
The corps started ramping up its releases in early May.
Then, in mid- and late May, it started to rain heavily in the Upper Missouri River Basin, with more rain expected.
On May 21, the corps was notified that 8 inches of rain had fallen in 48 hours in areas of Montana. It kept raining in Montana, where a record 3.12 inches fell in Billings, and the western Dakotas.
There was little the corps’ dams managers could do now but open the floodgates. The schedule of planned releases quickly accelerated – and kept changing, bewildering and frustrating local officials.
Crews scrambled to build emergency levees in Bismarck-Mandan and elsewhere in a mad race against the river.
A flood bigger than the dams, something that once seemed impossible, now was inevitable.
The peak releases from Garrison Dam, a torrent running 150,000 cubic feet per second, would be more than twice the previous record, set in 1975.
The peak flows would be sustained for two weeks in June, and the river would be above flood stage for several months.
Once protections were in place, there was nothing to do but wait as troubling questions nagged at officials and homeowners.
How high will the river rise? Will the levees hold? What should we do?
With a destructive flood on the way, homeowners in low-lying sections of Bismarck-Mandan nervously read elevation charts and compared them to the river forecasts.
Jim and Cathie Volk knew their home, in the fashionable Fox Island subdivision south of Bismarck, would flood.
Their house suffered minor flood damage in 2009, when an ice jam caused a flood that came and went within hours. Little did the Volks suspect then that the ice-jam flood, broken up by dynamite, was a portent of worse to come.
Based on the flood forecast, the Volks expected the main level of their home would have 2 feet of water.
To prevent damage, they removed their carpet, furniture, appliances and cabinets from the main floor. To keep his foundation from buckling, Jim, a semi-retired stockbroker, flooded their shallow basement crawlspace. “It was terribly painful to do,” he said.
The river crested at 19.23 feet, well below the 22 feet predicted, but 3 feet above flood stage for Fox Island, which once actually was an island.
A foot of water filled their garage but didn’t reach the Volks’ main floor. They’d built their home 2 feet higher than their builder recommended when they moved to Fox Island 16 years ago.
Jim Volk’s boyhood home in Mandan had flooded several times, including the 1952 flood, so he decided to take precautions, even though he had confidence in Garrison Dam.
Although their main floor escaped water damage, the couple confronted a major cleanup job. Spiders had moved in, and walls and other surfaces had to be scrubbed clean or painted.
“There’s so much cleaning to do when a house sets dormant for that many months,” Cathie Volk said of their five-month absence. “It’s like building a new house.”
When the river subsided in late summer, the Volks went to inspect the river delta that has formed from years of sediment buildup – blamed as one of the culprits in the 2009 flood.
Deltas and large sandbars exacerbate flooding because they diminish the capacity of the river channel.
“It’s much, much larger than it was,” Cathie Volk said, with dismay of the delta that has become an unwelcome neighbor. “It’s much bigger than anybody thought it was.”
As the enlarged delta off Fox Island attests, the Missouri River, its banks and floodplain, have been dramatically rearranged by the flood of 2011.
It will take years for the changes to become fully apparent, experts predict.
Joel Galloway, a hydrologist for the U.S. Geological Survey in Bismarck, has been keeping a close eye on the river during and after the flood.
In early fall, he went up in an airplane with colleagues for an aerial view of the transformation. From an altitude of 800 feet, Galloway could see ample signs of changes along the reach of the Missouri below Garrison Dam to the headwaters of Lake Oahe.
Some banks had eroded significantly. Some sandbars were wiped clean; elsewhere, new sandbars have formed.
Through Bismarck-Mandan, the record volume and high velocity of water significantly scoured the river channel, increasing its capacity.
That natural dredging of the channel, many agree, was largely responsible for the lower-than-expected flood crest.
But as the river’s level dropped after the flood, and as it slowed down, it began once again to deposit sediment in areas, Galloway said.
USGS has embarked on a study of the changes along the Missouri River from the 2011 flood, and the North Dakota State Water Commission also is studying the effects.
“We’re really in the early phases,” still compiling data, Galloway said of the USGS study.
“Ten years down the road, we could still be seeing the effects of this,” he said. “Those effects are going to be hard to overcome.”
A report by the North Dakota Game and Fish Department concluded that habitat along the Missouri River has changed profoundly as a result of the flood.
The least affected area likely is the portion of the river including Garrison Dam’s Lake Sakakawea and above.
The upper Missouri River in North Dakota experiences sediment deposits every spring from the free-flowing Yellowstone River, making the 2011 flood not so unusual.
But the 70-mile stretch south of Garrison Dam, including the channel through Bismarck-Mandan, is likely the most altered in North Dakota, in the Game and Fish analysis.
That segment of the river experienced unprecedented river volumes equaling or exceeding 100,000 cubic feet per second for 68 straight days.
“Extremely high releases over a prolonged period will greatly scour the river bed, and hundreds if not thousands of acres of bottomland will erode,” the report said. “In some cases, the main river channel itself may reclaim some of its former self by incising a new path of least resistance.”
In many ways, the flood of 2011 created a new Missouri River.
Garrison Dam’s spillway gates encountered a few hitches when they opened for the first time.
Sealant had to be reinforced in spots and later, after water was observed flaring on the spillway’s apron, officials shut the gates once again and discovered the water had chipped some of the concrete.
Quick-curing concrete was trucked in overnight for repairs. Once the initial problems were addressed, the floodgates and spillway performed as designed in their first real test, officials said.
In the midst of the flood, Todd Lindquist, operations manager for Garrison Dam, found himself reminding people who were angry over the huge releases of water that the spillway gates had been built for a reason.
Officials, including Gov. Jack Dalrymple and North Dakota’s congressional delegation, have questioned the corps’ response to the flood, and an independent review has been ordered.
A major critical theme has been that officials were too slow to react when it was clear the basin’s snowpack could leave little room to maneuver if heavy rains followed.
Before winter, officials in North Dakota asked for reassurances that the corps would be fully prepared for a possible spring flood in 2012. Some, including Sando, the state engineer, called for the corps to release more water from the reservoirs to create more flood storage capacity.
But the lower Missouri still remained above flood stage in early fall. Later, after residents and officials pleaded for the release of more water from the reservoirs to make more room for a possible flood this spring, the corps increased the flow.
The dams must be managed as a coordinated system for a river that runs more than 2,300 miles through the heart of the country.
Although Garrison and the other dams could not prevent widespread damage in the 2011 flood, the corps calculates that the dams prevented $44.2 billion in damage throughout the Missouri River system as of 2010. Garrison, which alone accounts for a third of the system’s flood storage, was credited with preventing $13.7 billion in damage.
As for criticisms that the corps could have avoided damaging flooding by acting more swiftly and aggressively, Lindquist said preliminary calculations show Garrison simply was overwhelmed.
Even emptying the reservoir – a drastic step no one would recommend – wouldn’t have been enough given the magnitude of runoff for the system, which was almost 1¼ times its previous record, Lindquist said.
“If Lake Sakakawea was empty, we still would have filled it one and a half times,” he said. “People don’t understand the volume.”
And people forget how quickly conditions can change. Just six years ago, at the end of a prolonged drought, Sakakawea fell to its record low level – almost 48 feet below its record peak in 2011.
Susan and John Boyce aren’t sure whether they’ll rebuild their flooded home in the Sandy River Drive area north of Bismarck.
With ground water tables still high, and the stubborn wet pattern showing no sign of fading, many around Bismarck-Mandan fear what spring has in store.
The Boyces have time for the questions to be resolved.
“If we weren’t able to purchase a condo, I don’t know what we’d do,” Susan Boyce said of her temporary Bismarck home. “We feel very fortunate.”
Just two years after their house was built, in 1995, homes in the Sandy River Drive area had to be built up an additional 2 feet. The Boyces aren’t sure it would be practical or affordable to raise their home.
“We’re still trying to do it one day at a time and do the wise thing,” Susan Boyce said.
A lot of people along the Missouri River, their eyes opened by the 2011 flood, are trying to do the same.
Patrick Springer reports for The Forum of Fargo-Moorhead.
"Living with Water" in print
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