System monitors flood-prone creeks
- By Eric Kulisch
- Jan 25, 2001
Creek Level Monitor
With rain forecast for the next few days, Palo Alto, Calif., city workers
and residents may turn to a new Web site to find out how fast their creeks
The Creek Level Monitor is a welcome warning tool for people who still vividly
remember when the San Francisquito, Matadoro and Adobe creeks overflowed
their banks in 1998, said John Ballard, who supervises the storm drain system
for the city's Department of Public Works.
At that time, policemen and other emergency personnel had to scramble
to bridges to check gauges and radio in the readings every 20 minutes or
Now the Web-based system has become an integral part of emergency management
"Local residents watch this very religiously," Ballard said. "We created
it so residents can get this information themselves."
After the 1998 flood, Palo Alto Public Works installed ultrasonic devices
on bridges and wired them to adjacent storm pump stations to provide remote
water-level measurements. The data is transferred by an existing communications
system that controls the pumps and made available on the Internet.
The dynamic creek monitor represents the creek beds at five bridge locations
graphically. Water levels are shown in blue. An accompanying line graph
shows creek, tide and flood basin levels for the preceding 12 hours. Other
data includes 24-hour and annual rainfall totals. There's even a Creek Cam at a bridge over West Bayshore Road.
The system also helps park rangers remotely monitor and maintain water
levels in the flood basin, which serves as a wildlife and bird sanctuary.
Using electric gates on a man-made levy, the rangers periodically allow
water from San Francisco Bay to flush the ecosystem to keep it from drying
Many agencies and flood districts have flood-prediction Web sites that
rely on historical data, but Ballard said, "I don't know of anybody else"
that provides current information. The Creek Level Monitor is updated every
Future plans call for the system to integrate data from rain gauges
in the regional watershed to help predict creek levels before they reach
critical levels, Ballard said.