Well, considering this is the Era of Sinkholes, they are right to be concerned.

Remember in the naughties, all the tunnels? There was always something in the news about a tunnel... under the US-Mexico border, someone escaping from jail via tunnel, huge bank heist via tunnel, Gaza's tunnels... they were everywhere.

The 2010's have been about sinkholes... Guatemala City, Florida 2 or 3 times already, a bunch in China, Bloomberg as "media money sinkhole", London late last year... so many holes.
We just can't fill them all...

Sending from his own mind to yours, here is Nino Savate with 'A Psychic Minute.'

Can I say, hello? This is Nino the mind-boggler with Occult In Your Head. Today, let's get into holes: The most mysterious, importantest and vaguest subject of them all.

The whole Earth might be called a hole, if you're on the inside, looking out. And whole golden cities might be hid at the bottom of a bottomless pit. Even wholesome humans have holes, though we're hardly whole at all. In fact, we're wholly hole-y. As the Holy Book says in the Book of Holes, Chapter 1: 'And they knew not their holes from an ass on the ground.'

Holes are positively attractive. Let's go inside one and see... (((echoes))) This is a typical hole. Not a hole in the wall, but a hole like a well. Well, well, what the Hell? That's the sun at the center of the Earth, and that's where this hole leads to. Heh-heh! What a nice, warm fire.

Next time, I'll think to you about gravity, and its opposite, comedy.
Until then, this is Nino saying, can I say, goodbye?

Bertha will finally spell the end of the viaduct, but not in a way anyone had foreseen, (oh but what a mighty queue of lawyers will stretch from here to the end of time)

And when the tunnel starts generating sinkholes and related anomalies beneath Harbor Steps & other downtown properties, great hilarity will reign over the fair city.

And when the tunnel is complete and big trucks are able to get their cargo more quickly to the pier, congestion is alleviated on I5, I will no expert no such gratitude from The Stranger.

As a West Seattlite I am under no illusion that once the tunneling under the viaduct begins, the viaduct will not be reopening again. We are basically fucked. But hey, maybe light rail in 12 years!?!

You have to admit it would be pretty ironic if Ed's tunnel wrecked havoc on the capital operated by the individuals who are probably his biggest donors. Here's hoping no bystanders get injured.

@5: go find the depth profiles for the tunnel. it will be too deep into glacial till by that time to undermine downtown buildings. they are at the trickiest part - through fill at shallow depths.

if a sinkhole opens under the viaduct, oh well. it should have come down 10 years ago.

@9 Don't bother telling that to the 'sky is falling' crowd. Their sky is already coming down in chunks of blue.

Y'know what else is a continuing source of frustration? People who keep writing articles about sinkholes. So. Last. Week.
@BerthaDeBlues

Are these new sinkholes? Or have they been growing underground since the Nisqually quake? And Bertha is just running into hollow cavities.