The Location:
A Brief History:
Vancouver is bounded on its north side by a large, deep inlet, ideal for shipping but a serious challenge for road and rail traffic. A series of bridges were built to cope, yet all the while the region (and traffic) continued to grow. Burrard Inlet already had the 1930's Lions Gate Bridge at the First Narrows, but the harbour's second narrows only had a 50-year old 2-lane lift-span to join Vancouver on the south side to North Vancouver opposite. At first, traffic was handled by a low, tilt-span bridge (also called a "bascule" bridge). This might have lasted except for the constant problem of large, heavy ships colliding with the low piers adjacent to the lifting span. In 1930 the bridge was knocked out of service for 4 years while the owner waited for repairs. Replacement parts and steel had to be shipped from the UK, a slow process. A slightly higher lift-span was added in 1938, but by then ships were larger and heavier, and continued colliding with the now repaired lift-span structure. Something had to be done since traffic was increasing, and repairs and maintenance were overwhelming the bridge owner.
*Now known as "The Ironworkers Memorial Second Narrows Crossing"
A Grand Idea:
After struggling with unending repairs and maintenance, the province made the decision to buy and replace the old bridge. The plan was to create a massive new, state-of-the-art, 6-lane bridge across the inlet, that would forever eliminate the tedious delays created when the lift-span had to be raised to let sea traffic pass. Plans were drawn, engineers reviewed the stresses and strains, and Dominion Bridge Company agreed to build it. It was going to be great! A huge, state-of-the-art, steel-arch bridge that would allow Vancouverites to cross back and forth quickly and easily at any time.
Disaster!
Unfortunately, on June 17, 1958, just as the new crossing was about to join hands across the narrows, something went horribly and unexpectedly wrong. The bridge collapsed. The province was stunned that something like this could happen in spite of the dedicated and conscientious work at all levels. Nineteen ironworkers went down in the collapse and drowned, pinned under thousands of tons of bent steel. How would anybody be able to figure out what went wrong after such a disaster?
"The Bridge" Film:
This film was created by Dominion Bridge as an almost inadvertant record of work progress. Behind the camera was a young draftsman, an energetic Peter Hall with a 16mm film camera, and a mandate to visit the bridge site and film the activity. Hall was not a professional film-maker. Regardless, he worked with the diligence of an enthusiastic apprentice, visiting and filming every day. After the horrendous failure of the bridge, and the painstaking rebuilding, Dominion Bridge was not interested in Hall's raw footage, so Hall carefuly looked after the unedited footage for the next 59 years until it resurfaced in 2021. This is the story that was assembled from historical records and Hall's film footage.
What Went Wrong?
The bridge itself was not an unusual construction project, it was just another gigantic steel span, made of rivetted steel beams and plates, typical of the time. Still, a bridge of this size required a massive amount of engineering analysis and calculation to get off the ground. Somehow, the post-mortem had to uncover what went wrong, even though much of the evidence was entombed 100 feet below the surface of the narrows, hidden in wicked rip-tides and currents. This video is the result, carefully assembled from historical scratch-pads, old notes, and (most important) years of amateur 16mm film by an apprentice draftsman, Peter Hall.
The Original Film Documentary courtesy of Peter Hall with the Assistance of George Orr, and commentary by Red Robinson
Recent bridge photos courtesy of Al Harvey at The Slide Farm
60 Years Later: The Engineering Post-mortem is completed:
"Collapse of the Second Narrows Bridge during Construction" Congress on Technical Advancement 2017 American Society of Civil Engineers (ASCE) Larry Betuzzi, M.ASCE P.Eng. Senior Engineer, WSP Canada Inc., Edmonton, AB, Canada T5S 2Y3:
Following the collapse, the British Columbia Government established a Royal Commission to examine the cause(s) of the collapse and the lessons learned as a result. After an extensive investigation, it was discovered that a temporary support (called a "false bent" by engineers), designed by an inexperienced engineer and inadequately checked by a senior engineer failed, which lead to the collapse of two spans.
Unfortunately, those gentlemen were on the bridge when it failed and both were killed. There are many valuable lessons from the Commission Reports related to the roles and responsibilities of contractor’s engineers in their design of the falsework that was intended to support a portion of span number 5 until the structural steel erection had reached Pier 15 and for the responsibilities and duties of engineers in post-disaster inspections and investigations. This [ASCE] presentation provide[s] an overview of the collapse and summarize[s] the effects of the disaster and the findings as to what caused the collapse. Some of these lessons [are] highlighted in this paper. It was a combination of engineering mistakes, flawed material and procedures, and inappropriate safety standards that resulted in failure. This [ASCE] paper focuses on failure during construction. In 1994, the bridge was officially renamed the “Ironworkers Memorial Second Narrows Crossing” in honour of the workers who died on that day."