An agreement on the construction of the Benicia-Martinez Bridge in the San Francisco Bay area has been met, allowing contractors to continue construction of the bridge under certain environmental requirements.
The five-lane bridge that spans the Carquinez Strait has been controversial because noise from pile driving was killing fish. The Strait is the lone outlet for migratory fish in California.
The recent agreement requires Caltrans to drive piles using an air bubble curtain device that dampens the sound waves. Authorities are unsure if the bubble curtain will work because of the strong tide in the strait, so construction must occur only during slack tide. If the curtain fails, more restrictions will be imposed, including a steel tube that would further absorb the impact of the pilings in the water. Constructing a steel casing could require up to 18 months.
“We’re assuming it’s going to work, assuming they work at slack tide,” Wayne White of the U.S. Fish and Wildlife Service in Sacramento told the San Francisco Chronicle.
Speculation over how long the project is going to last is rising. Since the project began, the estimated cost of the bridge has risen from $286 million in 1995 to $904 million due to problems with the Caltrans design, collapsing mud and drilling complications. For every day the project is delayed, the cost of could go up by $200,000, pushing the price over $1 billion dollars.
According to commissioner Mark De Saulnier, if the costs keep rising, the Metropolitan Transportation Commission may quit the project and start over with a less costly design, postponing the project for years.
To read our previous article on this topic, click the link in the column to the right.