Creative Commons/WarzauWynn

Boat traffic on San Francisco Bay during Fleet Week

Bay Area air pollution officials say something smells fishy about a decision by the city of San Francisco to sharply reduce its estimates of the numbers of spectator boats that will fill San Francisco Bay during America’s Cup racing events this year and next.

The city originally forecast that as many as 1,833 spectator boats would take to the bay during the America’s Cup World Series events in August and September this year. It also projected that 2,200 spectator boats would fill the bay during the higher-profile races in 2013.

But in a revised estimate released last month, the city now expects just 330 spectator boats in 2012 and 800 in 2013. It also reduced expectations for the number of cruise ships and race support boats in the bay. 

City officials say the new, lower estimates are the result of improved forecasting methods. The local air district, however, says the new projections appear to understate the number of boats that will take to the bay, and also underestimate the amount of pollution they will create.

San Francisco’s Board of Supervisors is scheduled Tuesday to consider appeals filed by environmental and neighborhood groups against the event’s environmental impact report, which was finalized last month. Jean Roggenkamp, the Bay Area Air Quality Management District’s pollution control officer, raised concerns about the lowered boat-count and pollution estimates in a five-page letter to the city's planning department.

Air pollution during the America’s Cup has become one of the major environmental concerns related to the regatta, which will match international teams of sailors on high-tech 45-foot and 72-foot catamarans. In part, that is because the city expects an influx of cruise ships and other boats during the events.

In addition, the Port of San Francisco plans to disconnect a new shoreside power system, already in operation, that pumps electricity into cruise ships docked at Pier 27. The power system allows ship captains to switch off polluting diesel engines as their vessels idle.

"That whole Pier 27/29 complex is being used as the America’s Cup village," said Brad Benson, special projects manager for the Port of San Francisco. "We’re not going to be using it for cruise berthing." 

To offset air pollution that will be created when the shoreside power supply is switched off, San Francisco plans to install a similar system for vessels docked along the southern waterfront at Pier 70, where supersize military and cruise ships idle as they are repaired.

But the air district, which provided a $1.9 million grant to help San Francisco install the shoreside power supply, says there are no guarantees in the city's published environmental documents that the Pier 70 project will move forward.

The air district also questioned San Francisco’s claim that air pollution will be less severe than originally anticipated. 

In her Dec. 15 letter to the city, Roggenkamp said the city failed to clearly state how it calculated the revised boat estimates, and she indicated that the city might need to come up with millions of dollars to help reduce air pollution caused by the regatta.

Michael Martin, San Francisco’s America’s Cup project director, said the revised estimates were based on a study of vessel traffic during Fleet Week, a popular annual military celebration best known for airplane flyovers.

“The consultants that prepared the first analysis stand by the second one,” Martin said. “We knew we needed to do some more analytical work to refine those numbers, so we did a more systematic boat count during this fall’s Fleet Week. We basically inflated that number by more than one-quarter to take a conservative estimate.”