Fortress of Louisbourg mounts defence against climate change
Parks Canada to raise Quay Wall by a metre to protect against flooding
Parks Canada is working to refortify the Fortress of Louisbourg in Cape Breton against assaults from the sea.
Work has started to build up the Quay Wall, which separates the reconstructed site from Louisbourg harbour.
"Over the years, certainly as the storms have battered the wood on the outside, it's stripped off some of the wood. So we're looking for ways to better protect that wall from the direct effects of the waves," said Parks Canada advisor David Ebert.
The wall is also a primary defence against flooding.
"We know that since the 18th century sea levels have risen about a metre," Ebert said. "We also know that, due to climate change, that we've got both more storms but also more intense storms."
The fortress was founded by the French in 1713, but fell to the English twice and was demolished in the 1760s. The Quay Wall was originally built during the fortress reconstruction in the early 1960s.
"The interesting thing was the decision was made at the time to give people a better view of the town of Louisbourg, they'd lower the wall by about a metre," said Ebert.
Now, some 50 years later, the rehabilitation project is raising the wall back up by that metre. The work will involve stripping the wall down to its interior concrete layer — which is still in good shape, Ebert said — then building a capping wall over that existing concrete and re-covering it with wood.
"They'll also be doing some armouring outside of the wall to give that wall a little bit of extra protection," he said.
Ebert said the step adjacent to the wall will also be raised a metre so visitors will still have the same view of the harbour, the town and the lighthouse.
Phase 1 of the project, which wrapped up in March, involved building two groynes (rock piles protruding from the shoreline) along Barrier Beach at the west end of the site in an effort to reduce erosion.
"We're starting to see a little bit of sediment trapped in there, so we're hopeful that's it's going to work well," said Ebert.
The work on the Quay Wall will be done in three sections, starting with the east end, and should be completed by March 2020. Construction will be paused during the summer to minimize the impact on visitors.
The federal government is spending $9.2 million on the flood-protection project.
Parks Canada is responsible for protecting nationally significant heritage sites for generations to come, said Ebert.
"So certainly what we're hoping is that as we see more and more impacts from climate change and sea level rise, that the site is safe and secure and visitors can still come and learn this really important part of Canadian history."
With files from Information Morning