Moving Bridge

December 31, 2012 by cynick | Posted in timelapse

Another of my hobbies is documenting the range of motion of movable bridges. Examples of such bridges that exist today are limited mostly to railroads, but a few notable highway survivors, such as the Stillwater Lift Bridge, still trundle along.

Most of these movable bridges can be photographed in motion at any time, but sometimes a bridge moves just once in its entire lifetime.

Still rare to this country is the concept of building bridges in some safe place and then transporting entire completed spans to their eventual resting spot, so when I learned that the main span of the new Mississippi River bridge at Hastings, Minnesota would be built in a field, barged a mile downriver, and cabled up into place, I knew I had to be there.

I made several trips to Hastings over the summer to observe the progress on the span’s construction; this photo gallery dates to about a month prior to the installation:

Sadly, I dropped the ball and missed the move from land to barge. The event was not highly publicized, and the local authorities took steps to prevent people from getting a good look.

It sat in the river, off to the side of the main channel, for a couple more weeks, ostensibly to wait for the weather to cooperate, but finally it was announced that the installation would take place between the 22nd and 24th of September.

Other than that they had obtained a 72 hour window to close the river and the existing highway bridge at that point to perform the installation, I had no idea what to expect.

I arrived on Saturday morning at 11am. The bridge had already been floated down from up near the dam, where it had been berthed since being moved onto the barges.

I found a good spot near the bank next to a piece of laser-sighted survey equipment, set up my tripod, programmed my intervalometer for a 30 second interval, and got comfortable.

An only-in-Minnesota fair-like atmosphere persisted all day long. A lone vendor, a guy in a trailer selling hotdogs, mini-donuts, and coffee, did great business.

The vibe reminded me of a similar occasion back in 1995: the implosion of the Montgomery Wards tower. It was a Sunday morning, at dawn, in, as I recall, below zero temps, and there were hundreds of people out on the streets to watch it go down. I remember a car with Nebraska plates pulling up, and someone from within hollering, “What’re y’all doing out here??” They couldn’t possibly have understood. It was a Minnesota thing.

As the afternoon went on, very little appeared to happen. The span moved once in a while, but the movements were so small that they could only be detected by keeping completely still and comparing the relative distance between a piece of the existing bridge and a piece of the new one. It was a bit like trying to detect the moon’s movement with the naked eye.

Families posed in front of the police tape and had their picture taken with the bridge in the background. I heard more than one kid grumble about how boring it all was, but I thought that they would probably be grateful, twenty years down the line, to have a record that they had been there The Day the Bridge Went Up.

Others became upset and demanded action; from whom, I’m not sure. I helpfully reminded many people that this thing wasn’t going on for their entertainment (although there was a bit of a laser light show at the end when they were doing their final measurements prior to raising the span!)

Misinformation abounded. Some of it was purely ridiculous, but some was just plausibly true enough that I began to wonder whether it was the product of some mischievous rumormonger.

Instead I realized that it was the result of collective armchair engineering. People, given nothing to watch and nothing to do, and wary of the dreaded “uncomfortable silence” will conjure up all manner of bullshit speculation, which would then be passed along to the next person, becoming more and more distorted along the way.

The longer I sat there, the more people got the idea I was somehow involved with the project, and would come over to ask me questions. I was privy to a bit of true information, since from time to time an engineer would come by to check the equipment nearby and would volunteer a little about what was happening, but I certainly didn’t have anything close to a full picture. After telling people what I knew, I’d then engage in the same kind of speculative talk as the others.

Eventually, the same ideas were repeated and recycled, and nothing new was suggested or seen.

A old man came by and said, “Did you know they made it a few inches too short?” Without missing a beat, I retorted, “Did you know that’s the sixth time I’ve heard that joke this hour?” His wife laughed and laughed. He did not.

I finished the book I had started. The crowd began to thin. I stuck around, knowing that ultimately, the timelapse video would tell a much more interesting tale than realtime reality.

By late afternoon, as I started getting the shakes from full bladder, empty stomach, and rapidly dropping mercury, I thought about packing it in, but stayed transfixed at the scene. Leaving then would seem a bit like turning off the car radio in the middle of a favorite song after arriving somewhere. You don’t go into the house, you sit there like an idiot singing or head-bopping along with the song until it’s over.

But then, as the sun was going down, my information source said that they were now working on the rail system to slide the span from the barges to the bottom of the pylons, and that this was a 12 hour operation.

That sounded like a good time to go home and recharge. I used pennies to mark the location of my tripod legs, packed up my gear, and biked back to my car.

Not deterred in the least by the boredom, or the rumors that the bridge wouldn’t be raised until Monday, I was back at the same spot by 10am on Sunday. It took about ten minutes to locate the pennies, and I recreated the shot within a pixel or two.

This time I came a little more prepared. I brought some bread and hummus, the Sunday NYT crossword, and more layers of clothing.

I sat there all day, going in and out of consciousness, meditating on a single leaf fragment on the ground, and listening for the clicks of my shutter.

Once again, by late afternoon, I was feeling the constraints of my bladder, but I didn’t feel like trusting my equipment to the crowd enough to steal away for a few minutes.

And then I was saved! My building’s caretaker, Mike, a longtime Hastings resident, happened by. I chatted with him for a while, and then asked if he’d watch my stuff for a few minutes.

I could barely walk, but I made it the hundred yards to the port-o-john, and came back seemingly pounds lighter.

The highlight of the day had been the painstaking move of the span off the barges to its place between the pylons, again, barely perceptible to the naked eye. In comparison, the work to hook the cables to the bridge went by in a flash.

But then nothing happened for hours. The talk was that raising the span was a five hour operation that would be completed by morning.

Now I had a choice to make. Surely, if I were to go home, and come back again, the span would be up, and I would have essentially wasted the whole weekend.

I decided to stay at least until I saw the bridge moving upward. An elderly gentleman took up a spot beside me, and we kept each other awake into the evening by noting every small thing that was happening, and postulating that after each thing that the bridge’s moving just had to be imminent.

At 9pm, he gave up and went home.

Another guy, who had his tripod set up nearby, came over to chat. We talked about all manner of topics for a few hours, which made the time go faster, but he, too, gave up. By then the temperature had dropped into the high 40s.

I was losing hope, and starting to entertain the idea of packing up, when lo! around midnight the bridge made its first tentative jerk skyward!

Reinvigorated, I decided to stay. But would I be able to last another five hours? Would my camera’s batteries?

As it turned out, the relative lack of wind made it possible to raise the bridge faster than had been thought, and it was completely in place by 3am. Orion had just come up over the bridge, surely symbolic of something, but of what I don’t know.

The camera’s batteries had gotten down to 15%, (a great test of the power consumption of my camera!), and after sitting there for 17 hours, with no food or drink over the previous twelve, my own personal batteries were somewhere south of that!

As I packed up, and made my slow, cold, stiff ride back to the car, I thought I had really achieved something, and I think the timelapse video bears that out. I’m currently looking into possibly getting it used as filler on public television, but until then, here’s an animated gif that contains the money shots: