It says Fortis Inc. (has agreed to pay $1.2 billion in cash for Teck's stake in the dam and related assets.
Under the deal, Teck will then be granted a 20-year lease to use the assets to produce power for its operations in Trail, B.C.
Teck will also have an option to extend the lease for another 10 years.
The agreement has several conditions, including approval by BC Hydro - which owns the remaining stake in the power generation operation.
Teck says it will pay Fortis a break fee if BC Hydro exercises its right of first offer under a co-ownership and operating agreement.
