Pier rehabilitation explained

August 12, 2022

Scaffolding and tarps are seen on a pier of the Mcdonald Bridge.

In late 2021, the Nova Scotia Utility and Review Board (NSURB) approved a toll increase to accommodate a 10-year, $280-million capital and maintenance budget for Halifax Harbour Bridges (HHB). As a public sector organization committed to transparency, HHB is publishing a series of articles outlining the details of each of the major budget components. In this article, we tackle pier rehabilitation.

Did you ever wonder what’s going on behind the blue-green netting that is occasionally wrapped around piers on the Macdonald Bridge?

Over the past decade, HHB has been rehabilitating concrete surfaces to address deficiencies and cracking to enhance service life.

In 2012, a detailed inspection of the Macdonald Bridge substructure and foundations identified the majority of the concrete was experiencing alkaline-fueled deterioration, coupled with cycling freezing and thawing damage.

A mitigation plan was put in place and so far, 14 piers, along with portions of the Halifax and Dartmouth abutments have been rehabilitated. HHB plans to complete rehabilitation work on all piers by 2028. Work on three piers (D3, D7, D8) which began this spring is expected to wrap up in November.

Concrete restoration projects are a highly complex process, with the scope of the effort based on the location of the respective pier or abutment

Environmental controls are a strict part of every tender issued by HHB. For concrete restoration, the green-blue netting serves to control dust, which is not only good for the environment, but also for the community that surrounds the piers.

All waste is disposed of in accordance with municipal guidelines. The chipping and blasting of the concrete “skin” can be loud, so HHB limits noise levels during inappropriate hours.

Here’s an inside look at how a concrete pier repair is carried out: