Bowstring bridge option dropped by council

A replica bowstring bridge is off the table when it comes to replacement of the St. David Street (Highway 6) bridge across the Grand River in downtown Fergus.

Following a special meeting on March 7, Centre Wellington council agreed to proceed instead with the staff-recommended option of replacing the superstructure and converting to semi-integral abutments.

This option includes the complete removal of the concrete deck, girders and cantilevers, while maintaining part of the existing abutments.

Prior to the decision, Kathy Baranski, chair of  Heritage Centre Wellington, endorsed the concept of a bowstring bridge to replace the current structure.

“After much consideration, Heritage Centre Wellington felt we had to suggest a different alternative to council,” Baranski said.

“At one time, not too long ago, a bridge was often seen as a source of civic pride and stood as a symbol of status and accomplishment.”

As such, she said bowstring bridges were landmarks and often defined an area or community of heritage significance.

Baranski noted local contractor and craftsman Charles Mattaini built over 50 bowstring bridges in the area and his work was well-known and admired outside Wellington County.

She said “the demolition of bowstring bridges and replacing them with more up-to-date bridges is seen by some as the sacrifice of heritage bridges at the altar of traffic efficiency. “

The bowstring bridge on St. David Street was built in 1924 and stood until its replacement in 1968 with the current structure.

Baranski noted recent information revealed the existing bridge could merit designation on its own as a rare cantilever bridge in Wellington County.

“Heritage Centre Wellington would just like to ask that council and staff formalize a process to do the heritage research before making a recommendation on design alternatives,” she said.

Baranski said Heritage Centre Wellington understands “it will be more expensive to construct a bowstring bridge, but we feel that amortizing the cost over the lifetime of the bridge, the cost will be manageable.”

She said the committee also understood the bridge would take longer to build, “but the slogan – worth waiting for – could be used to excite people about this project.”

In his report to council, Centre Wellington’s managing director of infrastructure services Colin Baker spoke to the Class Environmental Assessment on the bridge and his report, which recommended the preferred alternative of superstructure replacement and conversion to semi-integral abutments.

Of the current structure, Baker said “it’s pretty much at the end of its service life.”

Investigation of bridge replacement began in 2004 recognizing that road salts had penetrated deep into the deck. In 2012, the township undertook a detailed structural investigation and design report. At that time, a superstructure replacement was recommended.

A report was submitted to the Ministry of Transportation to demonstrate the urgent need, Baker said.

The Connecting Links program was cancelled in 2013, but when it was reinstated in January 2016, Centre Wellington applied for bridge funding based on replacement of the superstructure.

In April 2016, the township was notified it would receive a $2.2-million grant, so officials started a Class EA to address the severe deterioration of the bridge.

Baker said there was community consultation in addition to assessments of traffic and detour routes, cultural heritage, existing infrastructure, utility impacts and possible alternatives.

He added a number of unique features were incorporated into the bridge conceptual design (including a mid-span viewing area and options such as a black steel railing to offer contrast and decorative streetlights) to provide a unique landmark and sense of destination for residents and visitors as the gateway to downtown Fergus.

While he agreed the current structure is a rare example of a cantilever bridge – “structurally it is beginning to fail.”

Four options

With the inclusion of the Heritage Centre Wellington proposal, Baker said there were four options up for consideration.

1. Do nothing. This would leave the structure as is with no rehabilitation or replacement, which would eventually lead to bridge closure;

2. Concrete deck replacement. This would include the complete deck replacement with a reinforced concrete deck on the existing girders while maintaining the existing structure configuration;

3. Superstructure replacement and conversion to semi-integral abutments. This option includes the complete removal of the concrete deck, girders and cantilevers while maintaining part of the existing abutments, which will be modified to a semi-integral type;

4. Replace structure with a replica concrete bowstring on a concrete girder bridge. This option includes the complete removal of the concrete deck, girders, cantilevers, and widening of existing abutments and replacement with a concrete girder bridge including decorative bowstring structures.

Fergus BIA

Baker said township staff and its consultants had several discussions with downtown Fergus business owners about the project and their concerns.

Businesses stressed to the project team that:

– the construction should commence as early in 2018 as possible (i.e. after the 2017 Christmas shopping season);

– the duration of the bridge closure should be as short as possible; and

– additional signs should be installed to direct patrons to downtown businesses and parking areas during construction.

Next Steps

While there is still considerable work to be done, Baker stated if all went well construction would proceed from January to September 2018.

He said one of the major considerations is the Connecting Link program, which requires funds to be spent in 2018. With the project proposed, Baker said those deadlines could be met.

Council discussion

Councillor Kirk McElwain stated that while he hated losing the heritage aspect, “putting a bowstring bridge (in) would cost an extra $1-million.”

More importantly, he said, “moving to the bowstring bridge would mean an additional environmental assessment, which would take the project beyond 2018 and mean reapplying for a Connecting Link grant, which would not be guaranteed.”

Baker said the Connecting Link grant is only to fund projects undertaken in 2018 – “If the township cannot meet that commitment, the funding is lost.”

Baker said Centre Wellington would then have to reapply for funding, but there would be no guarantee of approval. He added, “The bowstring options put our schedule in jeopardy.”

McElwain asked if a bowstring facade could be considered.

Baker said the bridge would still have to be widened to incorporate the concrete arches, which triggers an additional environmental assessment and delays the project beyond 2018.

Councillor Stephen Kitras considered the replica bridge option as a “Potemkin village type arch – like a movie set.” He wondered if the arches could be built from another material such as fibre glass to provide the aesthetics.

Denis Hollands of Triton Engineering stated extra width to accommodate the arch would still be needed to maintain road widths, plus the sidewalks.

“It doesn’t matter whether it is made of fibre glass, cardboard or concrete,” said Hollands. He added regardless of material, the arches would require some structural aspect to withstand weather, wind and bridge vibrations.

Councillor Mary Lloyd said in 2016 the township invested in preserving the bowstring bridge on Irvine Street.

Baker said the rehab cost was just under $400,000 and work will be needed every 15 to 20 years to preserve it, at a “significant expense.”

Councillor Don Fisher said council’s information package suggests the current bridge to be of significant cultural heritage as well. Fisher asked whether it would have been better to have that information available during the public consultation process.

Baker stated that “since it was built in the 1960s, we initially didn’t think there was that cultural heritage value.”

Lloyd said if council chose not to endorse the staff recommended option, it could potentially affect the capital budget by $3 million – due to the $2 million in funding the township would lose, plus the additional $1 million to undertake the advanced work.

“I think it is important we make sure the public understands we are looking at this from all ways; not just the financial way but how it could impact businesses,” Lloyd said.

Fisher said, “It is very important in this community especially, that we need to be sensitive to heritage.” However, he pointed out work on the Irvine Street bridge was to preserve an existing bridge and history, whereas, “Here we would simply be replicating a bowstring bridge. It is a different thing.”

McElwain remained concerned recent bridge replacement plans have ignored heritage in many ways.

“We don’t seem to be showing the respect to heritage that we should be showing as a township – when we allow historical landmarks to be replaced because of the dollar value.” At the same time, he agreed there is a difference in that this would be a replica  bridge.

Councillor Steven VanLeeuwen said his preference would be to see a bowstring bridge, “But after looking at the information presented, it makes sense that we can’t choose it.”

He was pleased some heritage features are being incorporated into the new bridge.

Kitras also was interested in the heritage option “… but the clincher was losing the grant.”

Councillor Fred Morris hesitated calling this losing a grant. He said it’s  “more the province ducking its responsibility. While the province may call it a grant, it is a connecting link of Highway 6.”

Mayor Kelly Linton appreciated the work done on the project.

“I think this bridge will become an icon,” he said.

“Maybe in 30 years, (the new bridge) will be a heritage structure people are talking about – that’s just the nature of change over the years.”

Council subsequently adopted the staff recommendation.

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