I thought I'd jot down a few of my impressions while they're still in my mind...
When I was younger, I used to have these dreams where there were whole rows of tornadoes, one after another. I never thought that was actually possible till I saw a video a guy shot in the Midwest in the 90s of six relatively placid twisters all lined up in a lazy row along the horizon.
Same kind of thing with the bridges in Wellington, Waterloo, and Dufferin. I've seen a mere handful of bow arch bridges in my time. They're fairly rare now in Peel, Toronto, and York. The only ones that leap to mind are the Pottery Road bow arch that's still in service carrying southbound traffic across the Don River, and the Etobicoke Creek Middle Road bridge on the Toronto-Mississagua border that's been closed since the late 70s (second one of its kind in North America, and now the oldest surviving one: 1909). There are probably others but, again, they're scarce enough that they don't leap to mind.
Bow arch bridges further west, though, seem to have been all the rage a century ago, in the same way that pony truss bridges were once everywhere in York County, hereabouts. I think for every one we saw, we missed another, and probably at least as many again have vanished down the memory hole in the past 30 years. But I saw over a half a dozen out there in the space of a few hours, and all but one of them still in service. At least for now. We saw three or four places with boring recent bridges featuring plaques that proudly, even gratuitously, boasted of bow arches they'd replaced. My impression is that most of these bridges will disappear in the next generation. Roads will be paved and widened and "while you're at it,..." will probably doom several of them. With the Stone Road bridge set aside as their avatar, there's probably not much that's going to save the others.
With regard to the others: the Bailey bridge on Niska Road is in serious study for replacement. It was put up in 1974 as a temporary measure, and it's attracting far more use than was intended. People are using it to avoid the traffic on Stone Road to the north, and despite its low posted speed, people are just flying over it. As a one lane bridge, it poses a serious safety issue, and it's been the site of several fatalities over the years. So I'm glad we recorded it when we did because it seems to me the responsible thing to do, no matter what the neighbours say, is to either replace it with a wider span, or close it altogether.
Ditto the Perth Street wooden bridge. I don't know how many actual wooden bridges are still in use in southern Ontario, but there can't be many. You can see from the photos that this one's rough shape, and if it makes it to the 2020s, I'll be surprised. So, again, I'm glad we took the time to record it.
But for all that I think the most astonishing bridge it was my privilege to meet last weekend was the Buggy Lane bridge. It's the first time I can remember being on a genuine one-lane road that was still open and in good repair in Ontario, and for miles at that. And I mean a REAL one-laner... no one and a half lanes and squeezing past each other. Room for one vehicle, period. We kept encountering signs we weren't going to get to the bridge. No exit signs. Dead end signs. But no barriers, no signs telling us not to trespass as though the thing had been given over to private property... no, we pressed on, puzzled, to see what we'd see, and eventually came to the bridge, crossed it, and met an intersection with stop signs and everything. So what were all the tricky signs about? Still, the wooden decking of that bridge was the shakiest of all and again, I'll be surprised if people are still using it in a decade.