Dr. Jeff Ollerhead

A scientist who teaches at Mount Allison University is wondering why the federal and provincial governments are commissioning a year-long, $700,000 study to find ways of preventing flooding on the Chignecto Isthmus, the 20 kilometre strip of land that connects New Brunswick and Nova Scotia.

“It’s not clear to me why we need to spend this kind of money on doing another study,” says Jeff Ollerhead, a professor in the Mt. A. Geography and Environment Department.

He points out that a number of studies have already been done.

“It doesn’t take new science to know that there’s a problem,” Ollerhead says, “therefore, at what point are we actually going to start to plan the solutions?”

He was commenting on this week’s announcement that the New Brunswick government has chosen Wood Environment & Infrastructure Solutions to complete the study by mid-February 2021.

The international engineering company has been asked to come up with “three viable solutions” to protect key infrastructure that runs across the Tantramar Marshes including the TransCanada Highway, the CN rail line, electrical transmission towers and communications facilities such as fibre-op cable links.

Ollerhead says the study might be worthwhile if it quantifies the strengths and weaknesses of the dyke and aboiteaux systems that hold flood waters back.

“[But] my bias would have been towards spending more of the money on actually starting to work on solutions as opposed to studying the problem,” Ollerhead says.

“This study is all fine and dandy, but eventually you have to do something with the results and I haven’t heard any commitment that anybody will actually do anything with the results.”

MLA concerned too

Green MLA Megan Mitton

Green MLA Megan Mitton, who represents Memramcook-Tantramar in the New Brunswick legislature, says she’s worried too about another full year of study before anything is done to protect the transportation corridor as well as people’s homes and businesses in towns like Sackville.

“The federal and provincial governments have been moving much too slowly on this issue,” she says.

“I’m glad that action is being taken, but I’m worried that it’s going to be too little, too late because every year there’s a chance that the dykes will be overtopped.”

4 R’s as solutions

Meantime, Jeff Ollerhead notes that in coming up with possible solutions, the company conducting the study will have to choose among three options that scientists refer to as the 4 R’s.

“So, the four R’s are: option number one, raise and reinforce, essentially raise dykes, reinforce them, put in bigger aboiteaux, if you want to put it this way, harden the shoreline to a greater degree,” he says.

“Option number two is retreat. You’ve got a set of dykes, you move them back say, 300 metres which would typically move them a little further up the slope of the land,” he says.

“Option number three is relocate, so rather than trying to deal with the coastal defences, you take whatever the thing is that you’re protecting and you relocate it somewhere else.”

Ollerhead says the company conducting the study will likely recommend some combination of options one and two rather than recommend moving infrastructure like the highway or rail line away from the marshes to higher ground.

However, he says, there are other things to consider.

“In a hypothetical world, if you said, ‘well, gee we’re going to replace the aging, inefficient track with high-speed, electrified rail anyway,’ then maybe it doesn’t matter, maybe your plan is you put in new tracks somewhere else and eventually, you just let the other track go,” he says.

Ollerhead warns that something should have been done years ago because sea levels are constantly rising as shorelines subside and the situation gets worse every year.

He says it would be catastrophic if another storm such as the Saxby Gale of 1869 were to hit the Bay of Fundy.

“If that storm were to occur today, especially given that was 150 years ago and the land has subsided and the sea level has risen since then, if that same storm were to occur today, I expect the existing infrastructure would be pummelled probably into an unusable state,” Ollerhead concludes.

NB releases more details of study

The brief news release announcing the contract award for the $700,000 study gave few details.

But on Friday, the New Brunswick government sent Warktimes a copy of the original, 37-page document outlining the terms and conditions any company conducting the study must meet.

Here is an excerpt describing the “strategic importance” of protecting the Chignecto Isthmus transportation corridor:

The strategic importance of this infrastructure to all Atlantic Canada and indeed to the nation as a whole cannot be over stated. As an integral component of the Atlantic Canada Gateway and Trade Corridor (a federal/provincial designated system of major ports, marine terminals, international airports, key border crossings, and road and rail connections) it is the principal routing for all land based trade and passenger travel between Nova Scotia and New Brunswick and points west. The high voltage transmission lines are the primary connection to share and balance electrical generation between New Brunswick and Nova Scotia. Loss of the electrical transmission connection could produce significant economic and social impacts. As well, electrical exports from the Muskrat Falls hydro-electric facility in Labrador will be carried on these lines when they commence operations in 2019/20.

The transportation linkages are also critical to the Provinces of Prince Edward Island and Newfoundland and Labrador. In Prince Edward Island’s case, the TCH through the Chignecto Isthmus is the principal year-round route for trade and passenger travel to Nova Scotia. Similarly, for the Province of Newfoundland and Labrador all land based freight traffic must cross the Chignecto Isthmus for access to the Marine Atlantic ferry service or to the Oceanex direct water service from the Port of Halifax to St. John’s.

Previous studies have estimated the value of trade passing through the Chignecto Corridor at $50 million per day. Traffic counts at the NBDTI permanent counter near Aulac indicate annual average daily traffic (AADT) of 15,500 vehicles in 2016 with annual average daily truck traffic (AADTT) of 2,490 vehicles. There is also significant rail car traffic between NS and NB.

A combination of climatological induced sea level rise (1 to 5 metres) and coastal subsidence is forecast to threaten most coastal infrastructure in Atlantic Canada before the year 2100. The Chignecto Isthmus dykes and the infrastructure they protect are also at risk.

To read a longer excerpt that includes information about previous studies, click here.

Note: This latest study will be cost-shared with the federal government contributing $350,000 while the New Brunswick and Nova Scotia governments will provide $175,000 each.