Transcript Finding the payoff in reducing risks

Finding the payoff in reducing risks
Northwest Hydropower Association
February 2013
Bill Christman, PE
Engineering Services manager
Chelan County PUD
Wenatchee, WA
Earthquake
Lack of anti-burst wrapping
Lack of connection between
upper and lower vertical
elements
Cyprus Street Viaduct – Loma Prieta earthquake
Hurricane
Buildings in
known flood
zone –
mapped
before the
storm
Flooding in New York from Hurricane Sandy
Dam failure
Missing head cover
bolts
(known)
41 of 49 bolts
recovered had
fatigue cracks
10 years of
increasing
machine vibration
Sayano-Shushenskaya Hydro-electric Dam, Russia - 2009
Stadium collapse
Sequencing oversight in demolition – “tiny” wires removed too soon
University of Washington - 1987
Bridge collapse
Budget problems
Known weaknesses
Tacoma Narrows Bridge - 1940
Bridge collapse
Shop drawing
gusset plate
omission
New load w/o
verifying
demand/capacity
ratio
I-35W Bridge in Minneapolis, Minn. - 2007
Bridge collapse
Manhole covers
left open
Big storm causes
internal flooding
Lacey V. Murrow Floating Bridge
across Lake Washington – 1960, above,
and today, right.
Sound practice
Post-Folsom spill
gate risk reduction:
Monitoring and good
response to spill gate
bearing wear
Rocky Reach Dam, Columbia River, WA
Sound practice
Monitoring
and response
to increased
uplift
(Decrease in
foundation
drainage)
Rock Island Dam, Columbia River, WA
Sound practice
1961 – designed & built to withstand:
• 200 mph winds
• Magnitude 9.1 earthquake
Center of gravity is
5 feet above ground level
Space Needle
Seattle, Wash.
The higher the risk, the higher the cost
No ownership
in the results
No link to culture and
institutional knowledge