The new Government of Yukon has been made aware of the significant deteriorating condition of the Wareham Dam spillway at the Mayo Generating Station and is working closely with the Yukon Energy Corporation (YEC) to replace the spillway.
The government will be putting forward a plan to ensure critical remediation costs are not borne entirely by Yukon ratepayers.
In December 2023, an independent engineering assessment determined that the spillway had deteriorated beyond the point of repair. This assessment was confirmed by a second independent assessment undertaken by YEC.
On November 14, 2025, the Government of Yukon’s Environmental Compliance and Inspections unit issued an Inspector’s Direction to YEC under the Yukon Waters Act. This document provides important written confirmation of both the significance of the infrastructure risks and the urgency of the required response. Engineers have confirmed that temporary repairs are no longer an option to extend the life of the spillway.
The Inspector’s Direction requires measurable and timely action from YEC, including the development of a comprehensive risk management plan, adequate emergency preparedness measures and details regarding spillway management options and timelines. The Government of Yukon and the Yukon Energy Corporation have measures in place to reduce risks associated with the Wareham spillway until remediation work is complete. Yukon Energy Corporation has a comprehensive dam monitoring and surveillance program in place.
The Government of Yukon will continue to consult with the First Nation of Na-Cho Nyäk Dun and the Village of Mayo as activities progress to replace the spillway. In addition, the Yukon Emergency Measures Organization will continue to work with its partners in the community and utilities to conduct risk assessments and tabletop exercises.
As one of the Yukon’s three hydro facilities, the Mayo Hydro Facility is essential to providing dependable power year-round, generating 15 megawatts of renewable energy.
The Wareham Spillway replacement project is anticipated to cost over $150 million.
Our territory’s energy generation must be reliable, affordable and most importantly safe. Our government recognizes the serious concerns with the Wareham Dam spillway. We will work closely with Yukon Energy Corporation to address these concerns and strengthen our energy infrastructure for the future.
Tim Kucharuk
Cabinet Communications
867-335-2419
[email protected]
Andrew Anderson
Communications, Yukon Development Corporation
867-332-0138
[email protected]