FORT ST. JOHN, B.C. – BC Hydro is currently conducting large-scale renovations at its facilities in the BC Peace Region.
The WAC Bennett Dam, its attached GM Shrum generating station, and the Peace Canyon dam will all be undergoing upgrades to their facilities in the coming months and years.
The WAC Bennett Dam will see a number of projects underway, including upgrades to the dam’s core casings, upstream face rip-rap, and spillway gates and chutes.
The core casings are openings to the core of the dam used for survey instruments that were installed during original construction, and subsequently during repairs after a sinkhole appeared in the top of the dam in 1996. BC Hydro spokesman Bob Gammer says that the dam is one of the most-monitored facilities of its kind in the world. Crews plan to seal 15 open casings, and evaluate options to address an obstruction in another casing this year.
Crews are also continuing work from last year to resurface the dam’s concrete spillway, as well as upgrading mechanical and electrical systems in the dam’s spillway gates. Upgrades to the spillway gates of the Peace Canyon dam are also currently in the preliminary stage.
One of the largest projects at the dam is the upgrades to the dam’s rip-rap, which is a layer of boulders that protect the top sixty feet of the dam from erosion cause by wind, waves, and ice in Williston Lake. Hydro received approval for the project from the B.C. Utilities Commission in May of this year. The project was subject to regulatory review due to it costing more than $100 million. Crews should begin quarry development at the Sand Flat limestone site this summer. Placement of the rock will take place during the Spring when water levels in Williston lake are lowest, and is expected to be completed in 2019 or 2020.
Other projects underway are being done to improve the dam’s generating station, including replacing the 500 kV transmission line disconnect switches, upgrading five transformer exciters, upgrading the ten generator’s control systems, and upgrading the HVAC systems at both GM Shrum and Peace Canyon generating stations.