So I went down a rabbit hole of reading about the historic draw bridges around California’s Delta Region, which led me to this video of the Miner Slough Bridge opening. While the bridges on the main channel of the river open fairly regularly, this one on a relatively small slough sees hardly any boat traffic anymore. From what I understand it’s pretty much just opened once a year to test the mechanism, which is what I initially assumed was happening in this video. But no, it’s actually opening to let a sailboat through.
I assume busy drawbridges are regularly staffed and a mariner just has to radio the bridge operator to request that the bridge be opened. But in the case of Miner Slough Bridge, I doubt that’s the case. It looks like opening the bridge is a whole to do, and since there are no gates to stop car traffic CalTrans used trucks to block the road while the bridge was open. So how did this sailor, who looked to just be doing a pleasure cruise around the Delta, arrange to have them do this?
Farther up the river, the Knights Landing Bridge is another drawbridge that is pretty much only raised once a year to inspect bridge nowadays. But I assume if someone wanted to sail up the river they could similarly arrange to have it opened for them.
And re-watching the video I may have found the answer myself, at least for this specific bridge. I see now there’s a sign on the bridge that says “12 hours advance notice required for opening” and gives a phone number to call.
But feel free to discuss how this works for other bridges.
I live near the Delta, and we used to boat there a lot. This is how it used to work in the 1970s. Things may have changed with the advent of the internet and mobile phones.
Most (all?) of the bridges have signs on them instructing boaters where to call to request an opening. Of course, this requires some advance planning, so you generally make an appointment and a tender will be on site at the appointed hour. I don’t know if there’s a cost to it, or what it might be.
If the bridge carries a road it will usually be the relevant road authority, since any impact to traffic has to ultimately be approved by them. Road classifications on land also normally carry over across any bridges. Some bridges open only at set infrequent times to avoid disrupting traffic, others do a regular cycle and some will only open on demand.
Years ago I read about a company that was told that, due to flooding, they needed to open their drawbridge. And although they knew they had a bridge, they were unaware that it was a drawbridge
Decent bet that after a few (many?) years of disuse they were right. It wasn’t a drawbridge any more. At least not without significant expensive and time consuming renovation.
Some rotate horizontally, some pivot at one end, and some lift up at both ends carrying the span up between them. Cleveland has all of those types.
All of the movable bridges in Cleveland have a control house attached to them, but nowadays I think they’re all unmanned and remotely controlled. And we still get big ships through the Cuyahoga, so they all need to open on a regular basis.
There are many types of draw bridges. Some sink into the water to allow ship traffic to pass over them, some slide back horizontally, and some do exceedingly weird things:
I notice there were no gates on the Heatherwick Rolling bridge to prevent pedestrians to start crossing as it started to roll. I can’t imagine some skateboarders will try.
That’s cool and all, but it looks like being cool is the only reason for its existence. There’s another (permanent) walkway back next to the building, and that little inlet of water seems to serve no purpose other than to have a cool bridge over it.
In Chicago there are schedules to let boat traffic through. I live there and can see some bridges from my place. They only ever open on a schedule (there are many of them and each needs opening…they are not regularly staffed).
That’s just Chicago though. Might be different elsewhere.Chicago has more than a few drawbridges though. Maybe the most.
