Planning: Experts say steps must be taken to prevent further damage in the St. John River Valley

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OTTAWA - Brent Bishop's imposing home a stone's throw from the swollen St. John River stayed bone-dry through this spring's flooding, just as it did in the flood of 2004, and it wasn't luck.

Enlarge Photo

Keith Minchin/For the Telegraph-Journal

Brent and Sheila Bishop of Riverside Drive in Fredericton built their home beside the river but took precautions against flooding by elevating it above flood levels, ending up high and dry.

It was good planning.

In 2004, when Bishop built on Riverside Drive in Fredericton's Barker's Point district, he knew the mightiest river in the Maritimes would eventually rise again.

So he asked a surveyor to mark on a tree indicating how high the water had reached in 1973's historic flood. Then he brought in truckloads of fill until it reached the mark. Only then did Bishop pour his slab foundation on high ground.

A few days ago, his home remained a dry island in an inland sea created by the river overflowing its banks, Bishop knew he'd done the right thing.

"I thank God for giving me the wisdom to do it," he said.

Experts say it's an example of what must be done in anticipation of future floods occurring with greater frequency and severity because of climate change.

With floodwaters receding along the river valley, they argue the time has come not just to recover and rebuild, but also to re-evaluate how to live, plan and build on a flood plain.

It may be just another five years - not 35 - before the same factors (high snowfalls, a late spring thaw and heavy rain) that triggered this year's flood cause the next one, said Environment Canada senior climatologist David Phillips.

"It would be a mistake to say we can blame this particular flood on global warming," said Phillips.

"But what we saw this year may be a dress rehearsal for the kinds of extremes we'll see more often in the future."

Robert Tremblay, who lived several years in New Brunswick, is developing a climate-change adaptation strategy for the Insurance Bureau of Canada.

The recent flood is a perfect example of how engineers and planners are being forced to revise their assumptions about catastrophic events, he said.

Planning and construction on flood plains are typically based on the so-called "100-year flood," or the probability that those catastrophes will occur only once in a century.

But "this is the third once-in-100-years event in the last 35 years," said Tremblay, referring to St. John flooding in 1973, 2004 and this spring.

"The abnormalities of climate change mean we have to throw the old design criteria out the window," said Mike Riley, of Riley Environmental in Fredericton, a small consulting firm.

Some measures to mitigate flood damage can be expensive, but even projects with huge price tags pay off with every subsequent flood.

Manitoba spent $63 million back in the 1950s and 1960s to build the Red River Floodway, a 47-kilometre channel that diverts the flood-prone river around Winnipeg's eastern edge to Lake Winnipeg.

It was costly - but it saved Winnipeg from flooding 18 times. During 1997's flood alone, the floodway kept 80 per cent of the city from being flooded and 500,000 residents from being evacuated.

Manitoba and Ottawa are now spending $665 million to expand the floodway. It's estimated the work will prevent $12 billion in losses during a major flood.

Of all weather disasters, flood compensation has become the highest cost to the federal government, says the Institute for Catastrophic Loss Reduction at the University of Western Ontario.

Designing structures with climate change in mind is not new; the Confederation Bridge linking New Brunswick to Prince Edward Island, built more than a decade ago, incorporates certain features in anticipation of sea levels rising by one metre during its 100-year lifespan.

But like most of Canada's long-settled river valleys, the St. John River valley is host to thousands of older buildings scattered in dozens of communities.

Many were built on a flood plain to outdated standards; they're likely to be the source of millions of dollars in compensation claims under the program the provincial government announced last week.

In Fredericton, it's beyond the pale to think of moving the Lord Beaverbrook Hotel, jacking up the legislature or installing a dyke in front of the grand old homes along Waterloo Row.

"We cannot move downtown Fredericton out of the floodplain," said Tremblay.

But it may be time to consider flood control measures never seen as economical before, or to set more conditions upon future development.

"The number one thing I would suggest along the St. John River is sustainable planning," said Riley. "On the areas prone to flooding, we should stop building."

Unlike trying to prevent climate change by reducing greenhouse gases, adapting to climate change doesn't require the development and wholesale adoption of new technologies.

Broadly speaking, "the solutions are known," said Tremblay. "The challenge is one of prioritization and finances."

Certainly, flooding and other consequences of climate change are on the agenda of policy makers and academics.

In 2006, a 611-page Environment Canada study examined the likelihood of coastal storm surges becoming more severe than they were in 2000.

In January of that year, the largest storm surge on record in Atlantic Canada caused extensive flooding near Shediac.

Damage claims worth $1.5 million were approved by the Emergency Measures Organization. Just 10 months later, in October 2000, another storm surge caused the worst erosion in 40 years.

Climate change adaptation is getting more attention this very week.

A conference on the subject is being held in Saint John Thursday and Friday, bringing together scientists, engineers and policy makers. Speakers are coming from as far away as the United Kingdom to describe the practical steps they have taken to manage climate-change risks.

The event is to conclude with an effort to identify the priorities for action in Atlantic Canada.

And this week in Toronto, dozens of experts are attending an international symposium on flood defence.

Floods, say event organizers, affect about 520 million people a year, claim 25,000 lives and cost the global economy about $60 billion.

In the Canadian experience, flooding rarely results in loss of life but remains the most expensive weather-related disaster, says the Institute for Catastrophic Loss Reduction.

Said Phillips: "the fact a severe weather event occurs is not our fault but the fact it becomes a disaster often is.

"If we recognize the climate is changing, our policies, our urban design, our building codes, we need to revisit all of them and ask 'are our communities safe?'

"They may have been for the climate of the 1950s, 60s and 70s, but not for the climate of 2020 or 2050."

Back in Barker's Point, nobody needs to remind Brent Bishop about preparing for the worst.

A former realtor, Bishop recalls a lovely home nearby that would have fetched $180,000 or more a few years ago.

But it sat on low-lying ground on the river bank.

Listed for a long time, it sold for less than $100,000.

"Nobody wanted it," he said. "It had flooded."