Thursday, October 22, 2009

Slides and Tunnels

On the east side of our local mountains there is a nice polite river that has many names. At the top it’s the American River, joined by Morse and Mesatchee Creeks. A little further the Bumping River joins in and then the Little Naches. From there to the Yakima River it’s called the Naches River.

This valley shows many remnants of the last Ice Age when massive torrents of water from melting glaciers tore out a lot of basalt. The walls of the canyon are basalt but the floor is all worn rocks of many kinds. Experts can tell you which ones were shaped by river tumbling and which ones were shaped by glaciers.

Now you have some idea of the geology of the Naches River Valley. Pretty interesting. Also very scenic. There are pine, larch, fir, and cottonwood trees.
Last week a part of this scenic wonder subsided and cut off the highway and dammed up the Naches River. The location is an area called “Nile.” I don’t know why it’s called that.

There’s another tributary called Rattlesnake Creek. I know why on that one. It’s almost as big as the Naches and a lot of water goes through there.

Since the “slide” put a massive amount of rock and dirt in the river it decided to find an alternate route. See, rivers have a job to do, such as the Green River above the Howard Hanson Dam. Their job is filling up the oceans. They won’t stand for any halfhearted efforts to keep them from doing that.

Here’s a link to photos on WASHDOT http://www.flickr.com/photos/wastatednr/sets/72157622570021278/
You can go to WASHDOT home and click on Travel Alerts. Then NEWS and then stories about SR 410 and then select flickr in the list at the right to get to these photos. It’s amazing.

There should be a way to combine the Howard Hanson Dam issue and the Naches slide into a win-win. Nope; the tunnel boring machine is getting oiled up to dig a replacement for the Alaska Way Viaduct.

The TBM, as it’s called, will be put to work under Seattle. It might miss the bus tunnel already under there. We hope so.

Part of that project will be to replace or repair the seawall along the waterfront. This is important because the tunnel will go below sea level. Or the new tunnel could turn into a very long car wash – not really a good idea.

Most tunnels these days get a liner installed right behind the TBM. I saw that on the Discovery Channel. You should watch “Build it Bigger” with Danny. He’s a kick. But the hope is the tunnel liner will keep the water out even if the seawall doesn’t. But still a good seawall would keep downtown Seattle from getting its feet wet.

Anyway, Seattle (suburb of Newcastle) has some major projects coming up in transportation news. The Alaska Way Viaduct demolition, the 520 Bridge relocation to Tacoma, the East Link Light Rail connection to Bellevue, Redmond, and Enumclaw via Renton, plus the high water in the Auburn/Kent Valley this winter. All very interesting but has to wait until the election to see what kinds of nuts will be filling key positions.

Both the Mayor of Seattle and the King County Executive will be new. They could either help get this stuff going or tie it up for the next four years. Newcastle will get a library.

Al

1 comment:

Dave said...

Sounds like Newcstle is coming out ahead of Seattle :)