With the new bridge project underway, though mostly on paper at this stage (design details), keeping the old bridge safe enough to serve for another three years remains a task at hand. Rust never sleeps, of course, nowhere more so than on the wet coast, sitting astride a salt water harbour where the wind blows and the sea wash filter through the old structure. Compromised rivets pop up like measles on a two year old. Fixes will be more robust than band aids and bailing wire but the analogy is not too far from a harsh reality.
City staff and engineering consultants were out on the bridge Sunday, the 27th of March, chipping away at concrete to analyze rivet conditions along the steel members encased by the concrete counterweights - something no one has been able to look at for almost 90 years.
Starker still are unique points of failure that will be repeated throughout the superstructure. Everwhere where there are rivets under stress, allowing salt water mositure to seep in between sandwich plates of cheap steel, the integrity of bridge beams are increasingly being compromised. Close examination of the interconnectedness of every part of the machine should dispel any notion of a complete and durable refurbishment without taking the entire structure apart.
Trying to do it on site would turn the Inner Harbour into a tailings pond. A point of reference for marina opponents is the potential environmental impacts on the harbour from construction and operations, not to mention the disenfrachisement of people powered craft that enjoy the northwest shores of the harbour. Those are very valid concerns. By comparison, even repainting the bridge on site, a logistical nightmare on any movable bridge, and most problematic on bascule structures, would pose untold risks to the marine environment. Look closely at what is already shedding and the concern should become apparent.
One recent letter to the editor promoted the fiction that we didn't do our homework on the bridge. It's still a work in progress, but as the project moves forward we continue to confirm that the original findings of our condtion assessments have been followed by prudent and sustainable decisions.
Fresh pictures of our bridge in decline are newly posted in my flickr gallery at www.flickr.com/photos/luton/