The mess at Oroville Dam will have lots of dam safety lessons, but they will take time to learn. One important lesson, though, is staring us in the face:
Climate change is projected to yield both more extreme flood risks and greater drought risks.
That was Mike Dettinger and colleagues, writing last year in San Francisco Estuary and Watershed Science.
My thoughts in “this week’s” edition of jfleck’s water news. Avoid missing a single issue of my haphazardly written newsletter (hey, it’s free, eh?) by subscribing here.
it will be interesting to see what the investigation
of the failure reveals.
it’s not like they haven’t known the erosive capability
of water on concrete (Glen Canyon Dam Spillway
failure and repairs is an interesting story).
Note that the current event on the feather river is like a 100 year storm, (150,000 cfs) a 200 year flood would be 174,000 and a 500 year flood is thought to be 320,000 cfs. (I think based upon reading the periods are a bit long, because while we don’t know the flows back then there was the 1862 flood which drove folks out of Sacramento and other earlier floods. But it is likley that earlier floods did have higher volumes although 1850 floods may not have had the impact of later floods because hydralic mining in the Sierra had not yet started in a serious manner. Here is a link to the top 10 Ca floods of the 20th century; THE TOP TEN NORTHERN CALlFORNlA FLOODS or THE 20TH …
http://www.westernsnowconference.org/sites/westernsnowconference
the report seems to imply that flows on the feather at Orroville were higher than the inflows to Orroville lake this year in the 1960 event.
This is a typical situation that confronts water managers all over the world. Dams can create bad floods all on their own (and with help from water managers). Trying to increase water storage to undo all the impacts on water users and after a record dry period sets up the kind of scenario we see at Oroville. You can’t mess around with Mom Nature and not pay the price.