St. Marys council approves urgent culvert replacement on Queen Street West

Project will cost more than $600,000

By Galen Simmons, Local Journalism Initiative Reporter

Council has agreed to adjust the Town of St. Marys’ 2025 capital plan to help pay for the urgent replacement of a Queen Street West culvert after it was found to be undersized, a factor that has led to its deterioration and, if left as is, could have serious consequences related to traffic movement in town.

At the July 22 St. Marys council meeting, council approved the addition of the $602,500 replacement of a 1.8-metre corrugated steel culvert, part of the Bolton Municipal Drain that collects water in a tributary northwest of St. Marys and crosses the west end of town before discharging into the Thames River.

“We discovered some issues with the Queen Street West culvert … through inspection,” St. Marys infrastructure services manager Jeff Wolfe told councillors. “We brought in our engineer; we were concerned about the type of degradation, so we brought in an engineer to take a look to see what sort of timeline we might have before we got into some major works.

“They recommended immediate replacement as a result of it being Queen Street West, which is an arterial road. The concern was if there is a heavy rain or thaw over the winter that there could be erosion around the pipe, which could potentially create a failure, which would result in a road closure. Because of the limited interconnectedness of the road network on the west end of town and the impact it would have on motorists, the engineer recommended replacement.”

According to Wolfe’s research and conversations with neighbours, the culvert in question was installed at some point in the 1980s to replace a larger, failing culvert. During their investigation, the town’s engineer discovered the current culvert is undersized and has limited capacity. Based on capacity calculations completed by the engineer, it was found that for a rectangular structure, the culvert should be sized at four metres by two metres.

Several short-term repair options were considered to extend the life of the culvert to allow for construction in 2026 but were found to be costly with either further restrictions on flow or low confidence in effectiveness. Therefore, staff recommended a precast concrete box culvert be installed as opposed to other construction methods due to the longevity of that type of structure, the rapid nature of construction and the comparatively low annual cost of ownership relative to other construction methods. The new culvert will have a span distance greater than three metres.

“There would need to be a road closures (during installation), but it would be limited to a week where the contractor would need to remove the old culvert and then reinstall the precast concrete structure and get it at least to gravel where motorists could travel over it again, and there would likely be some modified version of traffic control following that,” Wolfe said.

Due to its significant cost, Wolfe said town staff have reworked the 2025 St. Marys capital budget, which previously included $400,000 for a municipal drain project on Queen Street East. As staff have been informed that project will not progress to its construction stage until 2026, staff recommended the reallocation of $360,000 from that project to the culvert replacement.

In addition, Wolfe said staff are using savings realized from other capital projects this year – $66,000 from the Elgin Street reconstruction, $65,000 from asphalt resurfacing and $25,000 from stormwater management improvements – as well as $86,500 from the town’s capital roads reserve to pay for the remainder of the culvert replacement.