The Linda levee was located in the wrong place, built poorly
and destined to fail, a Stanford University professor testified Thursday.
"The Linda levee posed a relatively high risk compared to most levees,"
said Richard Meehan. "It's a high-risk levee from 1911 until it failed
in 1986."
The levee "offered little resistance to seepage" and the resulting February
1986 disaster "was basically a seepage failure," he said. "The soil was
loose and unstable and very susceptible to seepage instability."
Meehan, a geotechnical consulting engineer who specializes in analyzing
engineering failures, testified on behalf of the 3,000 people and businesses
who sued the state and Reclamation District 784.
He testified in the 1991 trial that resulted in a judgment for the plaintiffs.
An appeals court overturned that verdict and ordered the retrial.
Meehan has engineering degrees from Massachusetts Institute of Technology
and Imperial College, University of London.
From 1969 to 1985, he was president of Earth Sciences Associates, a
consulting engineering firm specializing in environmental studies for large
engineering projects.
He has maintained a consulting engineering practice in Palo Alto and
taught at Stanford since the 1970s. He also has lectured at the University
of California, Berkeley, and MIT.
According to Meehan, the Linda levee, built in the early 1900s on the
existing Morrison Grade, pinched the river and "encroached well in the
Yuba River channel."
He estimated the levee was more than halfway across the river channel.
"You're changing the hydrology of the river," he said.
Putting the Linda levee so far into the channel increased the river's
velocity during high flows and exacerbated erosion, he said.
Rodent burrows, a constant problem for all levees, weakened the Linda
levee to an "especially severe degree," Meehan said. The burrows allow
water into the levee, eventually leading to failure.
To make matters worse, he said, the levee was built on hydraulic mining
debris - porous sand and silt - which had washed down the river.
The levee should have taken an alignment that "basically respects the
regime of the river," Meehan said.
He noted that a 1916 Reclamation Board report criticized an RD 784 levee
along the Feather River because of its proximity to a Levee District 1
levee.
"Normally, it is good practice to relocate levees when the levee is
subject to failure, or is threatening the levee on the other side of the
river," he said.
Meehan said the "composition and construction of the (Linda) levee was
not up to engineering at the time. The modifications failed to correct
these deficiencies."
The levee was upgraded periodically between 1911 and its 1986 collapse.
Prior to the '86 disaster, Meehan said, the levee was only "marginally
stable to begin with."
He suggested that the 1997 Arboga levee failure "is a good case history
that helps shed light on the '86 failure." Both levee collapses share "a
pattern or sequence," he said.
Roland Iverson Jr., a Marysville attorney representing RD 784 in the
'97 flood lawsuit, sat through some of Meehan's testimony.
Meehan may be asked to compare the two incidents when his testimony
resumes April 23. The trial continues Tuesday in Olivehurst at 4240 Dan
Ave.
