- Tidal Canal Dewatering for CalTrans
Interstate 880, Milpitas, CA (2002)
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A 12' high x 120' long AquaDam® was installed to keep this tidal canal dewatered while
the California Department of Transportation (CalTrans) widened this new overpass to
install new footings. The canal was approximately 90' wide.
Ecology blocks were used to back up the AquaDam® and lend it extra support during high tide.
Each ecology block was supposed to be wrapped in geotextile fabric to prevent damage to the
AquaDam®. This did not get accomplished on all of them. The far end of the AquaDam® is left
rolled up high on the bank.
This is tidal water in summer months, so storms were not a major consideration.
However, super-high tides coinciding with full moons happened twice during the
duration of the project. At this time, the AquaDam® had to be strong enough to
control these super-high tides, which were sometimes as much as 9' deep.
Most of the high tides (two per day) were only 6½' deep next to the AquaDam®.
At low tide, there is only 12" of water next to the AquaDam®. The white pipe
going over the AquaDam® is connected to a 2" electric pump to keep the work