TORONTO -- Ontario is taking a go-slow approach to one of its plans to ease traffic congestion, announcing a pilot project for a toll lane on the Queen Elizabeth Way between Oakville and Burlington.

Drivers who don't have any passengers will be allowed to pay a toll to use the high-occupancy vehicle lane on the 16.5 kilometre stretch of the QEW between Trafalgar Road and the Guelph Line that is meant for people who carpool.

The four-year QEW pilot project will start next summer, but the government won't announce how much the toll will be until next spring.

Transportation Minister Steven Del Duca said Ontario plans to follow a similar approach to the one taken in Utah, which charged $50 a month during its HOT pilot project before moving to a fully electronic toll system with variable rates.

"I want to stress that doesn't mean that I'm announcing that will be our price here in Ontario," he said. "We don't know yet, and have more analysis to do."

Ontario plans a network of electronic HOT lanes with "dynamic" pricing based on time of day and traffic flows, and would post rates on highway billboards.

"Whatever the rate would be when the enter they lane it stays at that for their balance of time in the lane," said Del Duca. "It gives the government and the system the chance to take into account what's happening in real time in order to deal with what we call traffic demand management."

The transportation minister said it would be "premature" to talk about possible revenue from the tolls "until we've landed on what the cost will be for motorists."

The government will limit the number of permits issued to drivers who want to buy their way into the QEW's carpool lane.

"We'll probably end up in the neighbourhood of roughly 1,000 permits in total, but that will be done in phases over time," said Del Duca.

Other HOV lanes around Toronto are "very well utilized," and it doesn't make sense to try and draw more cars into those lanes, he added.

"It would effectively make those HOV and HOT counterproductive because it would be just as jam packed" as other traffic lanes, added Del Duca.

A new HOV and HOT lane will be created on the extension of Highway 427 north from Highway 409 when it opens in 2021, but the province is not looking at turning the car pool lane on Highway 417 in Ottawa into a toll lane, at least not for now.

The Progressive Conservatives oppose adding tolls to highways that taxpayers have already paid for.

"It may be the QEW today, but we all know we'll be seeing tolls on the 400 series highways," warned PC transport critic Michael Harris.

The New Democrats said it's not fair to let the wealthy pay to ride alone in carpool lanes, which they call Lexus lanes.

"Are people who are well heeled going to be able to drive to work quicker while people who are a little bit less well off are going to be stuck in the slow lane," asked NDP Leader Andrea Horwath.