FARGO, N.D. - In the only major city on the Red River with no permanent flood protection, what climatologists call "the new normal" is no abstract concern.
Over the past five decades, an average spring in Fargo means the Red River surges up to a peak flow of 1,610 cubic feet per second, the equivalent of a tanker truckload of water rushing past the city with every tick of the clock.
This median presents no problem for North Dakota's largest city, where the channel capacity of the Red is nearly five times higher, at 7,660 CFS.
But the new normal on the prairies, like every other mid-continental climatic region on Earth, is a relative absence of normals. Whether the cause is man-made climate change or simply a cyclical swing in some poorly understood precipitation cycle, extremes appear to be getting more extreme in the centre of North America.
Fargo saw its normal go out the window in 1997, when a record snowpack in Minnesota resulted in swollen Red River tributaries such as the Otter Tail River and eventually a peak flow at Fargo of 28,000 CFS.
After a panicked scramble to raise levees and sandbag low-lying homes, Fargo survived the Flood Of The Century relatively unscathed. Grand Forks lay in ruins downstream, but Fargo was able to lick its wounds to the tune of a modest $5.2-million flood fight and started making plans to buy out low-lying homes.
But that wasn't enough in 2009, when the Red River peaked at another record flow, 29,300 CFS. Two years ago, the issue was unusual snowpack on the North Dakota side of the Red River drainage basin.
Fargo was better prepared in 2009, but still endured a mad eight-day scramble to continue raising the height of levees and build secondary dikes in the event those levees failed. U.S. weather forecasters continually adjusted their projections, testing the emotions and the resources of a city staff and flood-fighting volunteers.
"The problem was the rain, in both 1997 and 2009. The rain accelerated the melt. We've never had rain like that," said Fargo Mayor Dennis Walaker, the only big-city mayor in the Red River Valley with a professional flood-fighting background.
In 1997, as Fargo's director of operations and emergency co-ordinator, he led the city's frantic flood fight. Elected mayor in 2006, he used his technical prowess to play an unusually hands-on role in the 2009 battle, which saw the city lose only three properties to the Red River.
At 6-5, Walaker is a bear of a man who looks like he could single-handedly stop the Red River in its channel.
But this year, he's tired. The National Weather Service has asked Fargo to prepare for a peak Red River flow of 31,000 CFS this spring, just in case more rain - or a late-winter blizzard - hits the southern portion of the Red River drainage basin.
That means the city's 75-kilometre system of levees - already raised since 2009 - have to be adjusted to an even higher level, using an arsenal of flood-fighting materials and products.
This year, Fargo is augmenting 19 kilometres of permanent earth dikes and concrete flood walls with 56 kilometres of temporary levees made out of clay, sandbags, sand-filled Hesco bastions, taller sand-filled trap bags, inflatable water tubes known as aqua dams and asphalt-mounted temporary flood fences called aqua fences.
"The goal this year is to reduce the number of sandbags," said Walaker, referring to the array of other temporary flood-fighting devices.
The public is growing weary of sandbagging and volunteers can only do so much, as city staff must supervise the operation to prevent injuries from bag-filling equipment, Walaker said.
Since Feb. 14, when sandbag-filling commenced, volunteers have been able to stockpile 2.5 million sandbags. Fargo uses three Manitoba-designed, octopus-style sandbag-filling machines - two of its own and one on loan from Grand Forks.
It also plans to reuse 300,000 bags from 2009, which were stored beneath ultraviolet light-proof plastic sheeting to prevent their liners from breaking down.
Despite the increased efficiency of technology other than sandbags, Fargo has already spent $6 million this year on the flood fight, said city engineer Mark Bittner.
Since 1997, the city has spent $35 million on flood-fighting operations and another $141.5 million on capital costs, including $22.9 million to buy out approximately 250 low-lying properties, Bittner added.
Fifty of those properties were purchased after 2009 and some were torn down and replaced with higher dikes in recent weeks. Few waterfront homes remain in a riverfront peninsula in the Oak Grove neighbourhood, the site of the worst damage two years ago.
"In 2009, through herculean work in eight days, we wound up with only three properties damaged," Bittner said, proudly.
The irony is, Fargo may be a victim of its own flood-fighting success. Both Walaker and Bittner fear the U.S. federal government will not help fund permanent flood-protection until the city is destroyed, or at least suffers the same fate as Grand Forks in 1997.
"We're concerned the only way we'll be supported is if we lose," Bittner said.
As a direct result of the 1997 devastation, a $410-million program of buyouts and flood walls, partly funded by Washington, now protects Grand Forks and East Grand Forks, Minn. The 1997 deluge also led Manitoba and Ottawa to expand the Red River Floodway around Winnipeg, at a cost of $660 million.
Fargo, whose annual operating budget is only $200 million, is left spending millions every soggy season on temporary flood-fighting efforts.
Fargo devised a plan for a $1.5-billion diversion, similar to Duff's Ditch, albeit on the west side of town. But it will have to be scaled down because of complaints of adverse effects on communities both upstream and downstream, Bittner said.
It may be another 12 or 13 years before Fargo enjoys permanent flood protection, as a deficit-addled Washington weighs its financial options and North Dakota and Minnesota municipalities squabble about the size of the diversion.
West Fargo, Fargo's western suburb, is among those that oppose the course of the proposed channel.
The ongoing bickering annoys Walaker. "It's never-ending. It's 'Why me?' It's 'not in my backyard,' " he said, referring both to the mentality of Fargo's neighbours and a minority of Fargo residents who don't like to see dikes on their own properties.
"They're more interested than they used to be. They still remember 2009." Ordinary Fargo residents appear to support Walaker in his drive for a means of protecting Fargo from a one-in-500-year flood.
"I'd like to see something more permanent, because it takes up a lot of resources," said Larisa Bosserman, a university student who lives in a home immediately next to a newly raised levee.
If the levees ever fail, the Red won't swamp just riverside homes. The vast majority of properties east of Interstate 29 would be inundated, according to a map of a worst-case scenario for this year, when the snowpack is high on both the North Dakota and Minnesota sides of the drainage basin.
Walaker, however, doesn't expect the 2011 flood will match the height of the 2009 deluge, despite the worst-case-scenario forecast.
The U.S. Army Corps of Engineers is making room in upstream reservoirs. Late-winter precipitation has been moderate, he said.
"I would be shocked if it was as much as 2009," Walaker said.
That said, Fargo is getting used to getting surprised.