A small oil spill during Morro Bay’s $8.6 million dredging project was completely cleaned up by Nov. 12, after quick action to prevent its spread in the estuary, according to harbor officials.

A welded piece on the hydraulic excavator dredge broke, sending a clam-shaped bucket to the bottom of the shallow channel in front of the Embarcadero in the evening of Nov. 10. Four or five gallons of hydraulic fluid—biodegradable vegetable oil—spewed into the water.

“We immediately deployed our booms, and contacted every agency. We hired a clean-up company to make sure everything was taken care of,” said Nick Tietje, superintendent of the dredging project for AIS Construction, a Central Coast company.

“It was a fairly benign incident,” said Harbormaster Rick Algert.

AIS Construction brought in an excavator bucket to retrieve the clam bucket, according to Tietje.

The dredging project marks the first time the bay’s channels have been cleared out since 2001, and the first time a local company has won the contract. Tietje said he’s proud of his company’s “completely green” electric suction dredge, another piece of equipment being used in the deeper channels instead of a diesel-fueled dredge. Rather than emitting toxic diesel fumes and noise, the electric dredge—plugged into an outlet near the Morro Bay Power Plant—“just sits out there and hums,” he added.

Sand from the bay’s channels is being used to replenish beaches at Morro Strand and Montana de Oro state parks, after analysis of the sand by the U.S. Army Corps of Engineers concluded that it “should be acceptable.” Heavy metals and other substances in the sand are all within regulatory limits, according to the Corps, with the exception of elevated nickel concentrations, “probably due to serpentine soils in the watershed.”

The dredging project, which is paid for by federal stimulus funds, will take several months to complete.

—Kathy Johnston