Rehabilitation of Historic Blackfriars Bridge

Since the days of horse and buggy in 1875, before the invention of the lightbulb, Blackfriars Bridge has served the City of London, Canada, as an iconic symbol for the community and artisans.

The graceful arch truss represents the peak of wrought-iron construction, before the emergence of steel, and has become the oldest and longest-spanning arch-truss bridge of its type in North America.

Recognized as a Canadian Historic Place, and National Historic Civil Engineering Site, after 140 years, the question arose whether the bridge could survive and continue as a gateway into the downtown core, given the needs of modern-day vehicles, cyclists and pedestrians.

Using old-school and modern-day techniques to achieve an innovative and sustainable solution to preserve this historic bridge for future generations, a key priority was to preserve the original 1875 members, while upgrading where needed.

Wrought-iron contains impurities limited welding options. So to maintain historic integrity,
thousands hot rivets were used, a seldom-used technique in the past 75 years. Modern
button-headed bolts were supplemented to achieve a balance between heritage and structural requirements.

Replicas were created to match the original 1875 forged members, and lacing, with painstaking member-by-member adjustments to address dimensional variations in the originals.