Lake primarily during
extreme flooding, at a rate that
can be astounding. During the
1997-98 El Niño rains, scien-
tists at Jasper Ridge moni-
tored the sediment load of
Corte Madera Creek, the trib-
utary contributing most to the
sediment problem at Sears-
ville. “We were measuring in
terms of suspended loads
something on the order of
22,000 milligrams per liter,”
Cohen recalls. “You could go to
McDonald’s and get milk-
shakes thinner than that.”
Sediment settles dispro-
portionately in the alluvial fan
behind the dam, and vegeta-
tion amplifies the process by
stabilizing newly deposited
sediment, allowing the alluvi-
al fan to slowly creep up on the
dam. Today, the reservoir has
lost nearly 90 percent of its
original storage capacity of
1,000 acre-feet [nearly 326
million gallons]. The next big
erosion event could complete-
ly fill it with sediment.
If the dam were removed,
Freyberg warns, it’s not clear
what would happen to the 12
decades of sediment built up
behind it. An optimistic analysis suggests that most of the
increased sediment load would
end up in the Bay. At the other
extreme, all the sediment
could get locked up in the
creek, causing the creek to
grow shallower and the risk of
flooding to skyrocket.
“It’s not like you’re suddenly
allowing things to go back to
being natural,” Cohen argues.
“This is one of those dams that
has been around long enough
that it has really—in some
respects—integrated itself into
the landscape, and the streams
downstream and upstream
have calibrated to its presence.”
The question of what to do
with Searsville Dam is not a
new debate, and people like
Philippe Cohen and Matt
Stoecker have been playing
opposite sides for at least 10
years. The issue has received
sharpened attention since last
April, when the U. S. Fish and
Wildlife Service and the Nation-
al Oceanic and Atmospheric
Administration released the
draft version of Stanford’s pro-
posed Habitat Conservation
Plan [ hcp.stanford.edu] for
public comment.
‘ You can’t imagine how painful it is for me to say something
nice about a dam. ’
[including steelhead trout] and
protect and enhance habitat
on Stanford lands.” However,
beyond approving maintenance
dredging in the reservoir and
commissioning a feasibility
study for a fish passage at the
dam, the draft does not
address the dam structure.
Catherine Palter, associate
director of Stanford’s land use
and environmental planning
department and project manager for the conservation plan,
says the effects of dam modifications are too complicated
and risk-prone to include in
this plan. Stoecker’s group,
other environmental organizations and individuals have
strongly criticized this
approach in detailed critiques
given to the federal officials
scheduled to rule on the plan
sometime in 2011.
maintains that decisions like
these take “years and years
and years.”
Conflict over water has
defined U.S. history in many
ways, and many water con-
flicts start with a river and end
with a dam. “We literally
couldn’t support our popula-
tion” without many of them,
Freyberg says. Yet a serious
challenge looms. The U.S.
Army Corps of Engineers
identifies nearly 84,000 dams
in the country, more than one-
third of them built from 1950
to 1970. Most dams have a pro-
jected life of 25 to 50 years,
making the difficult decisions
about what to do with them
seem imminently crucial. Like
Searsville, each will have its
own idiosyncrasies that com-
plicate any vision of a clean
return to a better past.
The year 1922 marked the
opening of a recreational park
at Searsville Lake that served
as a weekend retreat for college students and locals. In
part to end conflicts between
park-goers and researchers
and students trying to study
the ecosystem, Stanford
closed the area in 1976. Little
remains of the old diving platform, and as the muddy bottom of the lake rises inch by
inch, there is little chance we
could relive the sepia-toned
vision it represents. Even less
likely is a return to the time
before man’s heavy hand forever changed rivers by clogging them up with dams.
The desire to return to
such a past reflects a common
conception that nature and
her rivers are good; man and
his dams are bad. Cohen’s
response: “I don’t like setting
up dichotomies of what people
do versus what is, quote-
unquote, natural, as somehow
being diametrically opposed. I
think those interactions are
more nuanced.”
Cohen also questions res-
toration as “somehow going
back to the past.” The past may
not be the best model for what
we will face in the future;
indeed, with Searsville,
visions of our past cannot be
our future reality, and the com-
mon notion of “restoration”
requires some rethinking.
After all, the only reason the
women on the Stanford diving
team stood dripping on the
cold concrete of Searsville Dam
was that the campus pools
were, of course, only for men. n
Nick Wenner is a senior
earth systems major. This article is adapted from Diving
Deeper at Searsville in Miller-McCune magazine.
