Things seem to be looking up for the troubled Walterdale Bridge project in Edmonton, Alberta. After months and months of waiting, the structure’s arch steel is on site and crews are now only waiting on steel for the bridge deck and shared-use path.
The arches for the new $155 million bridge were originally planned to be put in place late last summer, but late steel deliveries from Korea caused a one-year delay. Despite this, the city states that the bridge is on budget, with a cost of $155 million that includes $2.5 million in concept and preliminary engineering work.
The city’s construction contract contains provisions to offset delay costs. This project management approach transfers the risk of a delay to the contractor. As part of its contract, the project’s general contractor Acciona/Pacer Joint Venture (APJV) assumes the full project delivery risk, including penalties for schedule delays. Beginning in June, Acciona/Pacer Joint Venture, the general contractor on the new Walterdale Bridge started getting fined $10,000 per day.
The city anticipates the penalties bill could add up to more than $5 million. The completed bridge arches will span 206 metres and be 54 metres tall. The central arch segments have been assembled on the south side. They will be moved along tracks before being transferred to barges on the river. Once on the barges, the central segments will be floated across the river until one side of the arch rests on each berm. Temporary red lift towers installed on the berms will then lift the arches into place on top of the thrust blocks.
Since the river needs to be at least 2.1 metres deep in order to float the barges across, the contractor dredged the river bed.
Equipment included a long boom excavator working from the barges and an amphibious vehicle with a small boom excavator and hose that sucked up water and dirt from the river bottom. The retrieved sediments will be used as fill in Queen Elizabeth Park on the south side of the river. The heaviest arch piece weighs 125 tonnes and the amount of earth moved to date during construction is about 130,000 metres cubed. The weight of the central arches when they will be floated across the river is about 950 tonnes.
The new bridge will replace the old bridge, spanning the North Saskatchewan River to connect the intersection of Queen Elizabeth Park Road and Walterdale Hill on the river’s south side to the River Valley Road/Rossdale Road/105 Street intersection on the north side.
The steel pieces were fabricated and constructed by South Korea’s Daewoo International Corp., a company selected by Acciona-Pacer Joint Venture. According to the city, Korean crews had to put all the arch pieces together to ensure they fit well and to survey it during the trial assembly. Officials said the delays were not due to quality issues. The city as well as the contractor, followed quality control programs and have employees in Korea overseeing the work. The cause of the long fabrication time is due to the complexity of the bridge’s unique design, officials said.