U
C L A
Civil & Environmental Engineering Department
Presents
CEE
249 Seminar Series
California’s Levees: Then and Now
by
Timothy M. Wehling, P.E.
California Department of Water Resources
Sacramento, CA
November
3, 2009
4:00
– 5:00PM
Kinsey
Pavilion 1220B
Abstract
The future of California’s aging levee system depends in
part on our ability to understand and appreciate its history. The pioneering settlers of California started
building the levees 160 years ago during the Gold Rush. Farmers built levees to reclaim floodplains
and safeguard crops. Gold miners built
levees to keep rivers fast and narrow, not slow and wide, so that the rivers
would become self cleaning and wash the silt out to the Bay. Today, we have a massive system of levees
built with methods and materials not suitable for safeguarding vast housing
developments, and river capacities not ideal for safely passing design storm
events from reservoirs. Even with the
USACE engineered flood by-pass systems, climate change and the anticipated wetter
storms and faster spring snowmelts worsen the problem. That levee system is now the heart of
California’s water distribution system, and in turn the blood flow of the 6th
largest economy in the world.
California’s levees are deteriorating at an rapidly and require a major
overhaul. The State of California,
through the Department of Water Resources and the local levee districts have
begun improving the levee system, but the People’s commitment so far is only a
down payment compared to the resources needed to properly fix the system. This presentation focuses on the history of
California’s levees and the current levee improvement efforts. The ending of this story will unfold in the
next decade or so. Either the levees
will undergo an expensive remediation, or the system may fail when it’s finally
tested by the design event. The goal is
to better secure our State’s water infrastructure before it’s too late.
Biographical Sketch: Mr. Wehling is a Senior Engineer with the California Department of
Water Resources. He holds an MS degree in Geotechnical Engineering from U.C.
Davis.