Banff is one step closer to having a pedestrian bridge across the Bow River.
On Monday (July 18) council unanimously voted to construct a pedestrian bridge from Muskrat Street to Spray Avenue and sling new sewer pipes underneath it.
Politicians say they are essentially getting a pedestrian bridge for $400,000, instead of the previous estimate of $2 million for the bridge alone, by tying it into the sanitary pipes project.
“I think it’s a great example of out-of-the box thinking,” said Coun. Leslie Taylor.
“I’m so impressed we can get a pedestrian bridge people wanted, plus the sewer line, at less than what we have in the budget for the project.”
The estimated overall project cost, including the bridge, is around $680,000 less than the overall budget of the $6.35 million sewer pipe project.
The Bow River sanitary siphon consists of two steel pipes passing under the bed of the Bow River, running directly south from the pathway at the south end of Muskrat Street.
The pipes take all the sanitary waste from the north side of town under the river, and then by gravity down to the wastewater treatment plant.
The pipe crossing was installed sometime before 1968 and is considered to be at the end of its life span and was identified for replacement in 2007.
The Town is tying the pedestrian bridge into this project. The bridge would be able to accommodate an ambulance, but not a fire truck loaded with water.
Other options were considered, included securing the pipes to the existing vehicle bridge, while another considered an open cut, but came with too much environmental risk.
However, there are environmental risks even with this option, such as a blockage in the pipes resulting in overflow into the river, but the Town believes they can be dealt with through contingencies.
While the risk of complete failure of the sanitary system across the river is possible, they say it would be built with a minimum 100 per cent redundancy.
They say that would include spare crossing pipe, spare pumps, storage capacity in the collection chamber, grit removal system and an emergency generator to deal with a potential power outage.
“This type of arrangement is typical in many waste collection systems,” said Adrian Field, the Town of Banff’s environmental manager.
Field said this location is considered to provide an ideal link from Banff Avenue and Surprise Corner to the trails on the south side of the river to Bow Falls.
“As a result, travel on bike or on foot would be made safer and more appealing,” he said.
A pedestrian bridge at the south end of Muskrat Street was first identified as far back as the 1914 Mawson Plan.