The bridge is 1.2 kilometres long, opened in 1927, and has never, in its ninety-nine years of service, been fully painted end to end and then left alone. The maintenance authority that maintains it runs a continuous repainting program: a crew starts at one end, works steadily toward the other, and by the time it reaches the far side, years later, the end it started from needs repainting again. The bridge is never finished. It isn’t supposed to be.
“People assume we paint it because it looks nice,” said Colm Fahey, the maintenance authority’s senior coatings engineer. “The color is almost incidental. The paint is corrosion protection for structural steel that’s carrying live traffic loads. If the steel corrodes unchecked, you’re not looking at an aesthetic problem, you’re looking at a structural one, and steel bridges have failed from exactly that kind of neglect.”
Why the job never ends
The mathematics of the cycle explain the permanence. A full repaint of the bridge’s exposed steel, applying a modern multi-coat system over fully stripped and prepared steel, takes the current crew configuration approximately eight to nine years to complete end to end, according to figures the authority shared for this report, working within the constraints of weather windows, traffic management requirements, and containment systems needed to prevent old paint, some of it lead-based from repaints decades ago, from entering the water below. By the time the crew reaches the far tower, the section they started on nine years earlier has already been exposed to nearly a decade of salt air, temperature cycling, and UV degradation, and requires attention again, sometimes a full repaint, sometimes a targeted touch-up depending on how the coating has held up in that specific section’s exposure conditions.
The work happens inside sealed containment structures, tent-like enclosures rigged around each section under active work, both to control where blasting debris and old paint go and to allow the crew to work somewhat independent of weather. Old coatings are removed by abrasive blasting, and because some of the historical coatings on the bridge contain lead, all removed material is collected, tested, and disposed of as regulated waste rather than allowed to fall into the water or onto the roadway below, a containment and disposal requirement that adds significant time and cost compared to how the bridge would have been repainted in the decades before lead paint hazards were well understood.
What the crew is actually protecting against
Steel corrodes when exposed to oxygen and moisture, a chemical process that, left unaddressed, doesn’t just create surface rust, it can progressively reduce the effective thickness of structural members over years, which is what makes ongoing corrosion protection a genuinely structural maintenance issue rather than a cosmetic one. The multi-coat system currently used, a zinc-rich primer that provides sacrificial protection even if the outer coats are scratched, followed by an intermediate epoxy coat and a UV-resistant polyurethane topcoat, is designed to last fifteen to twenty-five years in a given section under normal exposure, which is why the full cycle can, in principle, keep pace with degradation if the crew maintains its pace.
The authority employs a dedicated coatings crew of eighteen people year-round specifically for this work, along with periodic outside contractors for sections requiring specialized rigging. Fahey has worked on the bridge for over twenty years and has, by his own account, painted every section of it at least twice in that time. He describes the job without any apparent frustration at its lack of an end point, in terms closer to how a gardener might describe tending something that’s always, by nature, going to need tending again.
“You don’t finish painting a bridge like this,” he says. “You maintain a state. The day we stop is the day it starts actually falling apart, not gradually and safely the way steel does when it’s protected, but the way it does when nobody’s watching it anymore.”