Historical Peak Flow Rates of the Merced River (2005 in Red)
This album is a selection of photos from a small flood in Yosemite Valley in May 2005.
There are so many amazing pictures of Yosemite, especially here on SummitPost, taken in all seasons. The images here are not very current, and many of them have poor lighting, bad white balance, I was trying to keep the camera dry, etc... They are definitely not works of art. But spring is here and perhaps some might be interested in seeing the valley in different circumstances than normal.
On May 16, 2005, my brother and I were camped in the Backpackers' campground in Yosemite, having just completed his first overnight trip to the top of Yosemite Fall. It had rained lightly all night, and we didn't think too much of it. We slept in the next day, past 9:00 AM, not motivated to get up until the rain stopped. After leaving the tent I was shocked to see Tenaya Creek had swollen and covered 1/3 of the campground.
Roads in and out of the valley were closed most of the day, and we had a blast running around taking photos and seeing new (and very temporary) waterfalls, flooded meadows, and getting generally soaked everywhere we went.
Information was poor. We had no idea when the roads would open (hours perhaps, some people thought days). At that moment I couldn't think of a better place anywhere to be trapped.
It was about a one day in ten year event. Flow rates at the Pohono Bridge at the west end of the valley recorded rates of 10,200 cfs, compared to a median peak annual flow rate of 4,680 cfs from 1917 (when record keeping began) until 2008. This rate has been exceed only nine times over this 92 year period.
Overall it was a very impressive experience seeing the valley in these conditions, though the flood was not especially damaging. The North Pines and Backpackers' Campgrounds needed repair and both were closed for a period of time, as was a portion of the Housekeeping Camp. As water receded roads reopened without damage, and buildings were largely unaffected. There are many signs around the valley regarding the flood of 1997, which was a much more serious event. It had 2.5 times the flow and closed the valley for over two months, causing $178 million in damage. If you are interested the Yosemite Association has an excellent writeup on the 1997 event