PEI

Coasts need living shorelines to stave off erosion, says P.E.I. researcher

Coastal erosion across P.E.I. is being evaluated for living shoreline techniques by researchers and members of the city's environment and sustainability departments, following the first implementation a year ago. Now, policy plans are underway.

Reinforcing waterfronts with concrete or boulders doesn’t work in the long run

Erin Nelson pointing to coastal erosion with hanging vegetation and the sea in the background.
Climate research assistant Erin Nelson points to an eroding P.E.I. coastline. (Kirk Pennell/CBC)

Researchers and watershed coordinators are working together to mitigate coastal erosion on P.E.I., using a set of powerful natural solutions to create what they call living shorelines. 

Living shorelines harness plants that naturally grow on P.E.I. to trap sand and topsoil and prevent the coast from eroding, says Erin Nelson, a climate research assistant with TransCoastal Adaptations, a centre for nature-based solutions that's based at Saint Mary's University in Nova Scotia.

"The purpose of my research is to try to have homeowners and property owners steer away from the hard armour and to really consider using natural methods," she said. 

In Nelson's words, "hard armour" refers to rigid material placed along the shoreline to deflect waves away from the site, including "unnatural stones and unnatural material" such as concrete or steel. 

Hard armour at Tea Hill Park. Grass and seaside.
This is an example of what researchers call 'hard armour' to reinforce a shoreline, used at Tea Hill Park in Stratford. (Kirk Pennell/CBC)

She said the practice can end up hurting adjacent properties, as well as being only a short-term solution for the property that a town or landowner is trying to protect. 

As it deflects the oncoming waves, hard armour causes seawater to hit neighbouring waterfront land even harder, whereas living shorelines absorb the waves, muting the force of the water along the entire shore. 

Living shorelines already underway

A project implemented at Tea Hill Park last year is demonstrating the benefits of living shorelines. Dead plant matter — in the form of hay bales — is making a difference there.

Living shoreline along Queen Elizabeth Hospital in Charlottetown. There are shrubs along the seaside.
Elements of a living shoreline, including hay bales, tree branches and shrubs, near the Queen Elizabeth Hospital in Charlottetown. (Submitted by Alistair Ozon)

"The hay bales have started being covered by sand, which means that it's trapping some of that sediment and helping create a more gradual slope from the land into the ocean," says Kaylee Busniuk, watershed coordinator with the Stratford Area Watershed Improvement Group.

P.E.I.'s history of deforestation weakened shorelines and made them more susceptible to coastal erosion, environmental researchers believe. 

"If you take away the trees, then it takes away those roots that are holding the soil in place," added Katie Sonier, an environmental sustainability coordinator with the Town of Stratford.

Erin Nelson showing freeable sand due to coastal erosion at QEP, Charlottetown
Erin Nelson points to unconsolidated sand that is susceptible to erosion at Queen Elizabeth Park in Charlottetown. (Kirk Pennell/CBC)

Busniuk said planting older trees along the coast is ideal because they already have an established root system and will grow to maturity more quickly.

"If people do have the funds, they can purchase trees that are already a few years old," she said.

Lawns and building placement

There are other ways homeowners can reduce shoreline erosion. 

Nelson warns people against mowing right up to the beach on shoreline properties because lawn grass has relatively shallow roots.

That can lead to overhanging vegetation and crumbling of coastal slopes.

Slumping grass indicating coastal erosion.
Slumping grass caused by coast erosion along the coast of Queen Elizabeth Park in Charlottetown. (Kirk Pennell/CBC)

Also, she added, "make sure you are building your sheds or houses far back so that your property or infrastructure won't be at risk for erosion." 

More damage predicted

Both women agree that the need for shoreline solutions will only grow in the decades to come.

"Through climate change, when we have higher tides and increased storms, the wave action is much stronger and it takes away more of the coast than just the natural process would," said Sonier. 

hay bales along the QEH, grass and a gazebo.
A living shoreline along the Queen Elizabeth Hospital shoreline at Murchison Lane and Riverside Drive. (Submitted by Alistair Ozon)

Busniuk noted weather pattern changes are resulting in a lot less sea-ice cover in the winter, "and that allows waves to batter the shoreline throughout the whole winter." 

When ice is thick enough to build up along the shore, it acts as a buffer for the energy of the waves, boosting protection along the shoreline. 

Policy changes urged

Nelson of TransCoastal Adaptations would like to see governments on the Island pushing nature-based solutions as opposed to the hard-armour approaches of the past. 

Alistair Ozon, water coordinator with the City of Charlottetown's environment and sustainability department, says it's an interesting time for policy development as more attention is paid to the environmental aspects of planning.

"I believe come next year, there's going to be work done to develop a new official plan," said Ozon. "The sustainability department will be developing a climate action plan."

Ozon says the city is building on the previous integrated community sustainability plan (ICSP), and the new ICSP set to be released next year will include living shorelines as a potential solution to coastal erosion.

Erin Nelson and Emma Doucette at Queen Elizabeth Park with the sea in the background.
Erin Nelson and Emma Doucette discuss how to evaluate the shoreline at Queen Elizabeth Park. (Kirk Pennell/CBC)

Corrections

  • A photo caption in this story originally misidentified Emma Doucette as Katie Sonier.
    Aug 19, 2022 3:19 PM AT