“Is there any worse soil in Portland that we could have built on?” she asked.
Wang, an engineer with Oregon’s Department of Geology and Mineral Industries, known as DOGAMI, wrote a report in 2013 that said an earthquake could cause this ground to liquefy, as she had just now demonstrated.
“The risk here is extreme,” she said. After an earthquake, “within 10, 20 seconds, the sand will turn into a thick, sandy soup.”
And that would be bad.
Soil liquefaction, as it’s known to geologists, can exacerbate shaking and destroy roads, buildings and underground pipes. If that happens in Portland, it could devastate supply lines for fuel, electricity and natural gas. It also could mean a major chemical spill into the Willamette River.
What exactly is the problem?
Oregon’s petroleum reserves, along with substations, key pipelines and natural gas storage, are highly concentrated in one stretch along the Willamette River. Scientists now know that stretch of land poses a higher seismic risk than other parts of the city.
DOGAMI modeling for a magnitude-9 earthquake shows most of the petroleum tanks in that area sit on soils the agency considers to have a medium to high probability of liquefaction. The area also is predicted to have very strong shaking.
Read all about it here:
Kayaking on this class V section will be permitted, and the management team there sounds quite reasonable about letting management evolve along with use. The use of this river section can be revoked if there is any paddling on Hetch Hetchy Reservoir, where boating is banned.
The run will start at Pothole Dome below Tuolumne Meadows and end at Pate Valley. Exact details about put-in, take-out, portage trails and landing/no-landing zone locations will be determined in the near future in consultation with the boating community, tribal interests and National Park Service resource experts. Boaters making the run will be required to carry their boats 3 miles to the put-in, and carry them 8 miles from the take-out at Pate Valley to the White Wolf trailhead.
Carrying your kayak 11 miles is hard. The info does not indicate that this section of river is a series of long slides over domes of granite. I do not know if anyone has been running it lately, but I do remember that Lars Holbek carried his boat most of the way and didn't want to do it again. I have HIKED down the Grand Canyon of the Tuolumne on a 3 day backpacking trip, and it was spectacular. A backpack trip might be a good way to scout the whitewater before committing in a boat. Though it is possible that those California boaters think nothing of this stuff. Looks hair to me.
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I landed in Portland today, went to a farmer's market to visit a friend who's getting hours for her Master Gardner certification--and to learn a thing or two about local plants and gardening. Meanwhile I was invited on a sea kayaking trip, so I rented a sea kayak, and got camping food. Sorted a few papers, prioritized. Felt glad to be getting out again. I'm not ready to go back into academic mole mode just yet. I feel more at home in my truck than I do in this office. But I will get this office working again soon.
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My birth town of Oak Ridge, Tennessee has a special (guilty but forgiven) connection to Japan. The laboratories in Oak Ridge were where the nuclear bombs that were dropped on Hiroshima and Nagasaki were created. When I visited the front page of the hometown paper this evening, there was this news ( from Japan )