Storms -> Rock falls

I know I promised acoustic ice blogging, but that will come in a minute. FINALLY, FINALLY it snowed. A lot. Many inches of rain down here, snow at 4000', and the Tioga Road closed due to snow on January 18th (although, it didn't snow until the 20th). And precipitation brings rock falls. We responded to one small event on the Hetch Hetchy road on Friday afternoon, but the really big event happened on Sunday night. A boulder the size of a house slid off the top of a cliff, bulldozed dozens of trees over, and removed a large chunk of the Big Oak Flat road. This road is the main route into Yosemite Valley from the SF Bay area - I've driven past here 100 times. Here's a shot of the boulder (at the bottom).



They called Greg, and Greg called me, so we went to have a look. We start from across the canyon and found that the best view was from a Wawona Tunnel portal, to see the source area (on top). There were clear bulldozed trees on the top and the bottom of the cliff, but it looks like the boulder cleared the large cliff entirely. Then we went over to the rock fall and had a look at the debris. Mostly we are assessing where the rock fall came from and whether more rocks are likely to come down in the near future. An inexact science... but we use our best educated judgement. In general, we don't want workers sent in there if there is a large instability, which does not look to be the case for this rock fall. Here's the road:





The workers started clearing the road today and may have a single lane running soon, although fixing the road will likely take months. There are many people who rely on that road and will be happy when it is fixed. In fact, one of our coworkers is bunking at our apartment since she lives on the other side of the road, and cannot get home easily. Here's a shot of some roadwork: