San Mateo City Councilman John Lee administered Groom's oath of office before she joined the board and ended her eight-year run on the San Mateo City Council, said Bill Chiang, a legislative aide to Supervisor Adrienne Tissier.
Groom has lived in District 2 for more than 30 years and takes the place of Jerry Hill, who announced his resignation in November 2008 after being elected to the 19th Assembly District seat.
Supervisor Mark Church was then selected as president of the board for 2009, and Supervisor Rich Gordon chosen as vice president, according to Chiang.
Church delivered a state-of-the-county address to a crowd of more than 200 at the meeting.
He emphasized the challenges ahead with the economy, especially following the hit the county took with the collapse of the Lehman Bros. firm in which the county had invested more than $150 million.
But he added that the county "has a much-deserved reputation throughout the state for being a well-run organization" and said the county has already implemented a five-year plan to eliminate its structural deficit.
Church also highlighted several specific issues the county needs to address, including health care, jail overcrowding and residential toxic waste.
