It appears the City is planning to keep the Fifth Street Bridge and refurbish it with a paint job. Although debate continues on the bridge and an additional pedestrian bridge. I have a few observations that may be helpful.
Once the paint is removed I would expect a more detailed inspection could be completed. If the bridge does have adequate strength and a significant life span remaining, the City could explore widening the walkways on either side.
The current concrete walkways could be widened or the concrete could be removed and replaced with lighter weight aluminum or timber walkways. The current railing could be retained and just moved to the outside so the appearance would remain similar. The current walkways are four to five feet wide, they could likely be widened to seven or eight feet relatively easily.
The bridge originally had to carry cars as well as heavy truck traffic. The current traffic is mainly cars and light trucks. Traffic is busy but likely well below the original design loading. The structure can probably handle more walkway loading.
The current walkway supports a cantilever out from the main structure. They also support two heavy 12-inch water lines on each side. The water lines could be moved onto the main structure. This would free up more sidewalk loading capacity.
The lane widths also were designed to handle wide trucks, so they should be more than adequate for the current traffic which is unlikely to change in the future.
If you walk across the bridge and look closely at the driving surface the concrete has very little cracking or fatigue evidence.
Many bridges have much more visible fatigue damage. This is a testament to how well built the structure was and how well it has withstood five decades of traffic.
It’s also an indication it has many years of life remaining.
Ian Farquharson PEng.