Elder bushes. Rock walls. Swathes of geotextiles.
From the banks of the Nashwaak River to the pebbly beaches of Sandy Point Road, New Brunswickers are using a variety of methods to fight slope failure — with varying success.
Slope failure, or erosion, happens when topsoil gets worn away because of water, fierce winds and human activity. The process causes irreparable damage to shoreline habitat and threatens homes, roads and beach access.
Preventing slope failure is tricky — but not impossible.
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An ecological restoration company in Bridgewater, N.S., says it has a better approach to preventing shoreline from being slowly nibbled away.
Kirsten Ellis of the company Helping Nature Heal offers some tips for people looking to curb soil erosion without interfering with the natural ecosystem.
1. Go natural
Ellis suggests using a combination of hay bales, loose hay, brush, woody debris and native plants to shore up erosion-prone banks.
"What we're trying to do is protect exposed soil and re-vegetate," she said, "so that it doesn't lose as much sediment and it stays stable."
Staking hay bales into place to cover the bank offers protection from wind and wave activity, as well as absorbing rainwater — a big contributor to shoreline erosion. The bales anchor the brush in place to cover the larger areas.
"As the hay decomposes, it grows, holds moisture and provides a good environment for plants to grow after a few months," said Ellis, adding native coastal species like elders, willows, bayberries and spirea can tolerate the salt conditions and spread by root.
"They grab onto the soil and hold it in place, and cover over the bank over time," Ellis said. "Even on really harsh, open, exposed coastlines, this is working really well."
2. Reconsider the rock wall
According to Ellis, the big boulders people often haul in to armour eroding coastline could be doing more harm than good.
"From an environmental perspective, those hard structures really impact the ecosystem," Ellis said.
As sea levels rise, salt marshes and seagrass beds naturally move inland — but "if there is a hard structure at the shore, they get squeezed between the rising ocean and the hard structure, and we lose those ecosystems," she said.
When a homeowner installs a rock wall, and then the beach proceeds to erode, "you have a 10 or 20-foot sheer rock face in between you and the shore," Ellis said. "It's difficult to access the coast and you lose the recreational opportunity."
Using hay, brush and plants, she said, both "provides habitat value and allows you to maintain the coastal processes that feed beaches and salt marshes."
3. Be patient
"The goal here is not to eliminate all erosion, which is impossible," said Ellis, "but to reduce it to a point where you're not losing huge chunks of land."
Fourteen years after Helping Nature Heal completed its first project, the shoreline "now looks like a full, natural forest," she said.
"We've also done bigger projects in P.E.I. and on the Northumberland Strait, where there are 30-foot sheer banks. We've been working on them for two or three years, and they're at the point now where they're really starting to re-vegetate."
It's important to remember that the "natural state is for it to be a stable slope and vegetated," she said. "We're looking to speed up that process by creating an environment where life can take hold."
4. An ounce of prevention
There's a lot at stake when it comes to soil erosion along the coast, particularly in areas where the shoreline is lined with homes and infrastructure, Ellis said.
"The tides on average are only getting higher," said Ellis. "The storms that we're exposed to are getting worse and more frequent. Our water is warmer."
Researching the best options now, she said, can prevent problems from becoming much worse in a matter of years.
"We have a lot to lose."