WHITEHORSE — The Yukon government says it will need to spend more than $150 million to replace an aging dam spillway.

A statement from the government says engineers have confirmed that temporary repairs are no longer an option to extend the life of the Wareham Dam Spillway in Mayo.

An order issued last month by Environment Yukon’s manager of environmental compliance and inspections says there is a “reasonable and credible risk of failure” of the spillway “with potential danger to persons, property, and the environment.”

It says the Yukon Energy Corp. must develop and implement a risk management plan by the end of the year that lays out measures to reduce risk and prepare for emergencies.

The corporation did not immediately respond to a request for comment, but an undated post on its website says damage to the concrete on the base of the spillway was discovered after high water levels in 2020 and repairs were completed but in December 2023, an engineering assessment found that the spillway needed to be replaced.

The website says the corporation has been working on solutions for two years and people should not be worried about flooding.

“While risks to public safety are increased with the spillway in its current condition, and will increase if this work is delayed, Yukon Energy has a fulsome dam monitoring and surveillance program in place, which would alert Yukon Energy staff of any issues before they occurred.”

The government statement says the Mayo Hydro Facility is essential to providing dependable power year-round, generating 15 megawatts of renewable energy.

It says it will continue to consult with the First Nation of Na-Cho Nyak Dun and the Village of Mayo and that the territory’s emergency measures organization will conduct risk assessments and tabletop exercises.

“Our government recognizes the serious concerns with the Wareham Dam spillway. We will work closely with Yukon Energy Corp. to address these concerns and strengthen our energy infrastructure for the future,” said Ted Laking, the minister responsible for the energy corporation, said in the statement.

This report by The Canadian Press was first published Dec. 5, 2025

The Canadian Press