October 13, 2008

BC MINISTRY OF TRANSPORTATION

The fate of the pontoons from the old Okanagan Lake bridge have become a bone of contention in Kelowna.

Pontoon controversy hinders bridge decommissioning

JEAN SORENSEN

correspondent

KELOWNA

Twelve concrete pontoons that floated the old Okanagan Lake Bridge for the past 50 years have been propping up a public debate on how to best dispose of their tons of concrete and rebar.

Environmentalists have queued up on one side and the construction industry is on the other.

A much-anticipated decision on the pontoons’ fate – with six in poor condition and six considered reusable - is expected soon.

British Columbia Ministry of Transport’s William R. Bennett Bridge project manager Jon Buckle said the option most favoured by SNC-Lavalin is sinking the pontoons along with two 21-metre bridge piers.

SNC-Lavalin is the contractor that is part of the Okanagan Lake Concession Partnership building the new Bennett bridge and decommissioning the old one.

Sinking the pontoons would be done in a controlled fashion within several deep portions of the lake that are 150 metres below the surface.

But that solution has raised environmental concerns, placing the pontoon disposal on hold until all parties reach agreement.

“We want to demonstrate that we are doing the right thing and working with the environmental agencies, especially if there are issues such as drinking water quality and fisheries,” Buckle said.

The pontoon debate began as the new William R. Bennett Bridge opened this spring and the decommissioning of the old span got under way.

Originally, the B.C. Ministry of Transportation received approval from the Federal Department of Fisheries and Oceans to sink six pontoons, which were deemed unsuitable for reuse, while the other six could have been used locally in a project such as a marina.

Buckle said that both the City of Kelowna and Westbank First Nation considered using the six pontoons, but finally decided against it.

“Our first choice would have been to reuse them,” said Buckle, as the options were considered, sinking the pontoons ranked as the second alternative for disposal.

However, the Kelowna-based representative for the Green Party and Canadian Earthcare Society, located in Kelowna, have both publicly challenged the sinking of the pontoons.

They pointed to environmental water quality concerns, fishery concerns and also the need for industry to demonstrate leadership in recycling its waste material.

The final alternative would be recycling the concrete and steel in the pontoons.

But, Buckle said, recycling the cement and steel is difficult as they would have to be pulled onto dry ground.

About 10 of the 12 pontoons are 60 metres long and they would have to be cut, while in the water, into smaller sections to be lifted.

In addition, the contractor did some impact studies and determined that the carbon emissions and the energy expended in breaking down the pontoons would outweigh the benefits of recycling.

Mike Reiner, a senior protections officer with the B.C. Ministry of Environment in Penticton, said a decision on disposing of the pontoons could be a month or two down the road.

Currently, the concerns of all parties are being evaluated.

“We are asking the proponents to lay out their concerns, whether they are drinking water or fisheries issues relating to the application,” he said.

Fisheries issues do not appear to loom as a major concern, as does waste management and drinking water qualities.

Hadyn Thomas, spokesperson for the B.C. Transport Ministry, stated in an e-mail that SNC-Lavalin, with the support of the province, is now seeking DFO approval to sink the remaining six pontoons.

Reiner said what we are looking at is the impact of the pontoons falling to the bottom of the lake and subsequent plume of sedimentation that may arise and could be taken into shoreline intakes for drinking water.

There is also a concern that the sediment that is stirred up has accumulated with run-off over 150 years of habitation and may contain years of pesticide residuals.

Buckle said the contractor is hoping to move forward on the pontoon disposal before winter storms occur.

“We have taken out the west approach span and cut it up. The steel was trucked to a steel recycling facility in Washington,” he said. “The next stage is the pontoons and finally there will be the lift span by the city (Kelowna side).”

Thomas stated that all pontoons would be cleaned and inspected prior to sinking, if authorized.

They are thought to be benign since they have been submerged for half a century with no impact.

“All necessary environmental approvals will be in place to ensure that the highest standards are met when disposing of the concrete portions of the old bridge,” Thomas maintained.

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