The two Expo Line track switches were first installed over 30 years ago and haven't been replaced - until now.
From June 3 to July 18, TransLink will be working to replace the switches which are an essential component that allows trains to be rerouted to different tracks. While the work is important, it will create a significant slowdown for commuters.
Over the six-week period, SkyTrain service will be temporarily reduced on a portion of the Expo Line because trains will only be able to travel on one side of the tracks between Scott Road and King George stations.
During the maintenance work, Surrey customers are encouraged to use Scott Road Station, as it will have the most frequent SkyTrain service in the area, and to plan for at least 20 minutes of extra travel time and crowded train cars.
The station will operate with near-normal peak service, but some trains stopping are expected to reach maximum capacity and some trains will terminate there.
Some trains will terminate at Gateway Station which will operate at 66 per cent of usual peak service, and some trains will terminate at Surrey Central Station which will operate at 50 per cent of usual peak service.
King George Station will operate at 33 per cent of usual peak service and some trains will continue there as normal.
TransLink promises additional SkyTrain staff will be on-site to assist customers at impacted stations but people are advised to look at station platform screens to ensure the train they are boarding will reach their destination.
This track maintenance work will not affect Expo Line travellers who aren't going as far as Surrey, not will it impact the Canada Line and Millennium Line.