Sea Level Rise Impacts Infrastructure Today

Unfortunately I didn’t have my phone with me earlier today when I ran past the crew working on the main train line from the Bay Area to Sacramento and then on to the rest of the United States.  But I wasn’t surprised to see them. Why?

The tracks run right along the shore of the Bay through Pinole. I’ve always loved this stretch of the train ride to Sacramento, but until recently I hadn’t fully comprehended just how close to shore they run.

One recent weekend we took the boys along the beach, past the salt marsh, and to a point where the track ballast is literally falling into the Bay.  The rack line that marks high tide was the give away — a recent tide had deposited debris on to the ballast.  That was the mark from a 6.9 foot tide on January 9th.

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A 6.9 foot high tide deposits debris on the mainline to Sacramento

Ten days later, the King Tide on January 21st hit +7.2 feet.  That’s another 4 inches above the line we saw. It’s no wonder then that Union Pacific crews were working diligently at that spot to repair the damage from repeated inundations.  It’s certain that they’ll be back with increasing frequency in the coming years and decades.

It had me thinking about the engineers who laid these tracks. They weren’t stupid. They understood where sea level was and would certainly have accounted for high tides. The sheltered location means they didn’t have to concern themselves about storm surges. But they didn’t have sea level rise in their engineering guides. Over the 100 years since these tracks were laid, sea level at the Golden Gate Bridge has increased by 8 inches.  It’s clear to me that this modest 6 inch rise explains Union Pacific’s conundrum today.

Looking ahead, it’s projected that sea level in the Bay may rise by as much as 55 inches.  I don’t think any amount of maintenance will save this section of track against that sort of change.  Short of raising it up on trestles, I don’t see where else they can thread the line through the crowded Bay Area. But at least raising it would enable the low lying open space that lies behind the line to be returned to wetlands to protect the adjacent communities.

And speaking of wetlands, my friends and colleagues at Save the Bay, have led a consortium that is seeking to pass a region-wide parcel tax to raise funds for Bay land restoration. One of the key arguments for passing the $12 parcel tax, which will raise $500 million over 20 years, is that restoration is desperately needed to protect the infrastructure that rings the bay.  In the coming weeks I’ll be looking more closely at the measure, and in particular exploring how it can help my local community prepare for sea level rise.

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Trains are fun: but sticks are way cooler.

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