Wetland restoration, Wetlands

Dam safety saves the day

The Hilliardton Marsh restoration

April 06, 2026

Wetland restoration isn’t a “one and done” deal. At Ducks Unlimited Canada (DUC), the real work often happens during the years of quiet oversight that follow.

Many of the wetlands we manage rely on low earth berms and other civil works to maintain water levels. This infrastructure requires constant upkeep, which is where our dam safety program comes in.

By monitoring structural integrity and water levels, our engineering team ensures these habitats can handle ever-changing conditions. Last summer, this vigilance proved its value at a beloved marsh in northeastern Ontario.

Viewing platform at Hilliardton Marsh. © DUC

Spanning 1,800 acres (728 hectares), Hilliardton Marsh is a provincially and continentally significant wetland. Before our restoration efforts in the 1990s, this landscape was dry and provided virtually no habitat. Today, it is a different story. The marsh and its surrounding grasses are home to 600 species, from migrating waterfowl to local mammals and fish. It also serves as an outdoor classroom through the Hilliardton Marsh Research & Education Centre, a DUC Wetland Centre of Excellence where the public learns about conservation firsthand.

Black tern, a migratory species that nests in large freshwater wetlands. © DUC

Protecting this site was a priority, but in conservation, speed must be balanced with care. When our engineers discovered a slump on the downstream side of the dam, we knew we had to act—but we had to do it on “bird time.”

After collaborating with Hilliardton champion and volunteer Bruce Murphy, we identified that the specific area requiring work was home to migrating black terns. To ensure their nesting cycle wasn’t disrupted, our team adjusted the schedule, waiting for the birds to finish their season. Once the coast was clear, local contractors moved in. Aided by a thorough design plan and a window of good weather, we completed the structural restoration in just two weeks.

The final stages of the slump repair. © DUC

In an era of unpredictable climate patterns, DUC values this kind of adaptive management. By combining rigorous engineering with local partnerships and flexible timelines, we ensure restoration is done well, and at the right time for the species that depend on us.

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