Here's some bad news for commuters who drive or ride the GO bus between Hamilton and Toronto each day — your trek is about to take longer.

Starting on Monday, some lanes on the Gardiner Expressway will be closed due to construction. The roadwork is expected to wrap up in December 2016, but crews will take a break in July 2015 for the Pan Am Games.

GO Transit says the closures will affect travel times on at least three of its bus routes, including No. 16, which runs between Union Station in Toronto and the Hamilton GO Centre on Hunter Street East.

Delays reported Monday morning lasted at least 30 minutes during rush hour.

Go Transit said in a statement on its website that "buses should remain en-route, with slight detours as required," it said.

To keep-up-to date on the construction, go to the City of Toronto's expressway and major route closures website.