Curley: Sound Transit will triple dip on I-90 bridge price

Shocking news: In order to get the choo-choo train across the I-90 bridge, Sound Transit will have to dip deeper into our contingency plan. How much more? $225 million.

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Here’s the thing. This shouldn’t be a surprise. If you’ve talked to any structural engineer, never in the history of anything being constructed, has anyone tried to take a floating bridge and place a hard train track over the top of it.

As George Kargianis and Phil Talmadge wrote in The Seattle Times a decade ago, the weight of the rails and equipment mean that the bridge would be at 98 percent of its load-carrying capacity, leaving a 2-percent safety factor. Thus, if there is some type of weather condition, or just wear and tear on the bridge, you’ll eventually have the thing crash into the water — again.

What’s my co-host Tom Tangney’s take on all this? “It’s pretty cool. The scientific engineering behind this is truly astonishing.”

But they haven’t done it yet. On paper, yes, it is cool. The science is absolutely incredible. But is it necessary? The amount of money that someone can continue to throw at a project is endless.

Think about this: Eventually, we might get the train to go across the bridge, but could we have found a more cost effective way to move 2 percent of the commuters? Why not a bus? Then you don’t have to spend the additional $250 million in order to somehow connect the two pieces of floating bridge with giant cables.

So, of course, Tom counters: “This will happen without causing any delays or a tax increase! You have a contingency fund set up and this doesn’t take all of the contingency funds. That’s why we have contingency funds. So the fact that they’re not asking for a tax increase and it won’t cause delays, is something to be remarked on as well.”

My retort: If that contingency fund had not been used, where would that money go?

My point is that past performance is a pretty good indication of what’s coming. Every time Sound Transit builds something, it is either over budget or way past the delivery date. And this is another example: They underestimated the budget on something that has never been done before.

Mark the time and date: The Sound Transit folks will come back to us again and say they need more money out of the contingency plan to do something else on the I-90 bridge.

Will I get a chance to say I told you so?

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