A new lane on the the Alex Fraser Bridge — and the strange vehicle that will switch the lane's direction twice a day — will cut about 20 minutes off the daily commute for motorists travelling over the bridge during both morning and afternoon rush hours, according to officials.

The bridge, which connects North Delta with Richmond and New Westminster, is heavily travelled and often becomes congested.

Beginning next week, however, the new centre lane will switch to northbound travel during the morning rush hour and southbound during the afternoon commute.

"Folks coming home from work southbound, will save at least 12 minutes, maybe 16 minutes a day ... People heading to work in the mornings will save six minutes and maybe even more," said Ravi Kahlon, the MLA for Delta-North at a demonstration of the new system on Thursday.

About 120,000 motorists cross the Alex Fraser Bridge each day, according to Ravi Kahlon, the MLA for Delta-North. (Rafferty Baker/CBC)

Kahlon, who said 120,000 people cross the bridge each day, added that motorists have already been enjoying the extra southbound lane, as the shoulders and other lanes have been narrowed to make space, but the alternating lane system has yet to begin.

The new system is based around something called a Road Zipper — a huge, strange, yellow vehicle with a cockpit on both ends. The Road Zipper will cross the Alex Fraser at 4:30 a.m. each morning to prepare for the northbound commute, and then again at 11:30 a.m. before the afternoon rush south.

It works by straddling the special highway divider in the centre of the bridge. As it travels over the bridge, it picks the divider up from one side of the new lane and drops it onto the other side. The process takes about 20 minutes each time, according to Kahlon.

The system is already used elsewhere, including on San Francisco's Golden Gate Bridge.

He said each segment of the special highway divider weighs about 680 kilograms, so in terms of safety, if should work the same as concrete dividers.

A new highway divider has already been installed on the Alex Fraser Bridge. It's designed to be moved across the lane by the Road Zipper vehicle, giving the direction with heavy rush hour traffic an extra lane. (Rafferty Baker/CBC)

The Road Zipper system, is part of a broader Alex Fraser Bridge improvement project, which will include upgrades to cycling infrastructure, changes to roads before and after the crossing, and reinforcements added to the bridge to strengthen it for the weight of the additional new lane.

The entire project has a budget of $70 million, with just over half the cost covered by the B.C. government, while the federal government picks up the rest. The speed limit will permanently be lowered to 70 km/h as part of the Alex Fraser Bridge improvement project.

Ravi Kahlon, the MLA for Delta-North, speaks to members of the media at a demonstration of the Road Zipper system on Thursday. (Rafferty Baker/CBC)

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