The B.C. NDP says it won't make a decision on how it will upgrade or replace the 59-year-old Massey Tunnel until the fall of 2020.

Transportation Minister Claire Trevena has ruled out a 10-lane bridge as a solution but says all other options are still on the table. She said the planned bridge project was flawed from the start, but a smaller bridge and tunnel improvements could reduce congestion and improve the crossing.

Watch Trevena explain why the 10-lane bridge proposal was flawed:

The B.C. government says more study is needed on replacement options for the 59-year-old Massey Tunnel. 1:28

The previous B.C. Liberal government started preliminary work on a 10-lane bridge between Richmond and Delta in 2017 but the New Democrats cancelled the $3.5 billion project shortly after they were elected.

The NDP hired engineer Stan Cowdell last year to study the best options to ease traffic congestion at one of the worst bottlenecks in the province.

Cowdell's report, which was released Monday morning, recommends further study into the construction of a smaller bridge, upgrading the existing tunnel or building a new tunnel.

It says the government should re-examine the entire project to ensure it reduces future traffic congestion and provides enhanced public transit infrastructure. Richmond's council had complained about the massive bridge project taking over agricultural and park lands, but the review says any replacement will still encroach on those lands.

'Understandably frustrated'

"People are understandably frustrated with the gridlock on the Highway 99 corridor," Trevena said Monday.

"Had the options been carefully and objectively considered before the 10-lane bridge project, we would be much closer to solving the congestion in a way that works for everyone."

Cowdell says the province should investigate whether an eight-lane immersed tube tunnel should be built.

A similar project that links Hong Kong and Macau was recently completed.

Trevena says she will be begin consulting with stakeholders on the project in the new year.

While those consultations take place, Trevena says the province will spend $40 million for immediate safety upgrades to the tunnel, such as improving the lighting and resurfacing Highway 99 between Steveston Highway and the Highway 17 Interchange.

Monday's news earned swift criticism from the Opposition, who dismissed it as a "non-announcement." Delta South Liberal MLA Ian Paton told reporters he was stunned.

"The NDP has failed 85,000 of my people who live south of the Fraser, people that are in the trucking industry, commuters that want to get home to their families for dinner," Paton said.

"They have been stuck in this tunnel with the worst congestion in B.C. for year after year after year, and this announcement this morning has done nothing to alleviate this issue."

Working together

Richmond Mayor Malcolm Brodie is a longtime proponent of twinning the existing tunnel, and Delta was the only municipality in Metro Vancouver to support the B.C. Liberal's vision for a 10-lane bridge.

The mayors of both cities, however, now say they are willing to put their differences aside to find a solution.

"The problem is at both ends of the tunnel — the Delta side and the Richmond side," said Delta Mayor George Harvie.

"We need to work together to make sure the province gets moving at fixing this congestion."

Brodie says he has already had a constructive conversation with Harvie, and he looks forward to meeting soon with other mayors from communities south of the Fraser.

"I'm very hopeful that we can come to some kind of a satisfactory conclusion," he said.

"Or, if we can't come to a satisfactory conclusion, we can at least define what the issues are and have them resolved one way or the other."

Academic says one-size-fits-all bridge 'a loser'

Anthony Perl, a professor of political science and urban planning at Simon Fraser University, believes abandoning the 10-lane bridge plan makes sense if the region is to develop more affordable transportation.

He suggested, in an interview with On The Coast host Gloria Macarenko, that it might be best to refurbish the current tunnel and look at expanding it to specifically serve trucks, public transport, cars and even passenger trains as needed.

"By keeping what we have, making it better, and then looking at other options, we can come up with a custom solution," he said, offering the example of Downtown Seattle's train-and-bus-only tunnel.

"We need to have infrastructure that can do more than one thing. And that's why that 10-lane mega-bridge was a loser."

In the meantime, he added, mobility pricing or tolls could get some drivers to reconsider using public transit.

With files from CBC Radio One's On The Coast