By Tom Peters

Plans by Halifax Harbour Bridges (HHB) to re-deck the harbour’s two spans over the next dozen years will include a project to raise both spans to accommodate container vessels with containers stacked high passing under the bridges. The Angus L. Macdonald Bridge, opened in 1955, will undergo the re-decking in 2015/16 and the same work on the A. Murray MacKay Bridge, opened in 1970, is tentatively scheduled to start in 2023, said HHB’s Alison MacDonald.

The engineering and prep work for the Macdonald bridge is already underway and actual construction cost for that project is $150 million, said MacDonald. “Halifax Harbour Bridges has a number of options with respect to the cabling system and structure of the Macdonald bridge which includes one that will actually result in the deck being elevated from its current position by approximately two metres,” said Halifax Port Authority’s George Malec. “Raising the deck adds about $1.5 million to the cost and Halifax Port Authority has agreed to cover that cost,” MacDonald said. “Air draft right now is consistently around 51 metres and we are seeing vessels transit consistently around 47 to 48 metres. Minimum required air draft under the bridges is 1.35 metres,” said Malec.

“The real prize is the second bridge (MacKay) re-decking. The Macdonald bridge is about half a metre lower now than the MacKay. When the Macdonald is re-decked it will be two metres higher than now which means we can immediately add half a metre to our air draft. When the MacKay is done, we will look to raise that by 1.5 metres, so the overall net gain is going to be 1.5 metres for both bridges,” said Malec.

OOCL vessels, with a capacity of about 6,000 TEUs (twenty-foot equivalent units), going to the Fairview Cove terminal, are the tallest that now pass under the spans. “They are about the tallest in the world in their class but we are very confident with the studies we have done, larger-TEU ships can easily be accommodated. They are wider but not higher. Right now, 8,000-plus-TEU ships can comfortably transit (under the bridges),” said Malec. “Actual top mast height is mainly the issue and some of the 10,000- and 12,000-TEU vessels being built are having retractable antennas which will make them more flexible,” he said.

The New York/New Jersey Port Authority is working on a similar project to raise the Bayonne Bridge by approximately 20 metres to accommodate the larger ships of the future. Projected cost of that project, expected to be completed in late 2015, is US$1 billion.