Tunnels and Guns

If this is your first visit, please read "Introduction".

Today I feel the need for a short rant on two subjects.

The first is the hostage situation in Sydney. There are two questions to be asked:

1.   How did a known nut case acquire a shot gun in a country with draconian gun control laws?

2.   What would the outcome have been had one of those hostages had a 9mm under their jacket?

It is a hackneyed phrase, but if guns are outlawed, only outlaws will have guns.


The second subject is the Highway 99 tunnel along the Seattle water front.

I am not an engineer, I have no access to special knowledge, but I knew, and predicted, that the water front tunnel was going to be a giant boondoggle.

I do have some knowledge of the characteristics of that water front from the perspective of an historian, and from what I know having spent three years working for a geotechnical engineering firm.

When Seattle was first settled there was very little flat land at the water front.  The hills that we all enjoy climbing descended almost directly into Elliott Bay.  There were buildings, streets and wharves built on pilings out over the water, as well as railroad tracks built on low trestles.

Beginning in 1909, Denny Hill, which once stood roughly where the Seattle Center is now, was sluiced down into Elliott Bay along the water front to create the flat land that now exists between the foot of the downtown hills and the current water front. The series of projects was completed in 1911. The soil is highly granular (sand, gravel), which means intruded salt water and ground water are present and contribute to the structure of the soil. If you pump that water out, settling will occur within the regrade area. That is not rocket science, folks. What is in today's news was 100% predictable.

Guess what. When the 1909-1911 project was underway the contractors did not bother to remove any improvements that would not extend above the final grade. That area is full of the remains of buildings and the pilings on which they stood. If Bertha is stopped by an 8" thin wall steel pipe, imagine when she hits 10-12" fir pilings that have been sitting in an anaerobic environment for over 100 years.

More fun.  The story goes that sometime in the 1890's a steam locomotive was being shipped from Alaska to Washington Iron Works for rebuilding and sale. In the process of attempting to move the locomotive from the barge to dry land, it got dropped in the Bay. According to the various accounts, it was not deemed cost-effective to retrieve the loco. So, if the story is true (there is evidence both ways), that locomotive now lies somewhere in the re-grade area.

I knew all this when the tunnel project was first proposed, and I made the prediction, on FaceBook, that, if attempted, it would be a boondoggle.

When the project got approved, I wondered how they would proceed. Though not a tunneling expert, I KNEW, that a boring machine would not work. There is simply too much debris in that fill.

I also KNEW that the traditional method of working a face would be very difficult because of the granular nature of the soils and the presence of large quantities of ground water and intruded salt water.

I figured that, from a design standpoint, the only method that would work was cut and cover. But that would involve disrupting much of the water front activity for as long as it took to build the tunnel.  I figured that was economically impractical, at best.

I don't think Bertha will be able to complete the job. So the City (tax payers) and/or the State (tax payers) will shell out bags of hard-earned dollars to remove Bertha.

My prediction is that the project will either be abandoned and another approach taken, or the tunnel project will continue, but construction will be cut and cover, to major detriment to the businesses along the water front.

No matter what happens, us tax payers are on the hook for large sums of money for a failed project.