Mary McCosker was born and raised in Lafayette, California, served on the Lafayette School Board for 13 years, is on the Board of the Friends of the Lafayette Library, and is president of the Lafayette Historical Society (LHS). At the speaker event, she will sell copies of Building the Caldecott Tunnel, which she co- wrote with Mary Solon, at the reduced price of $20, payable in cash or by check.
McCosker will talk about travel between Alameda and Contra Costa Counties prior to 1903, and then construction of the tunnels: Kennedy Tunnel in 1903 (above today's Caldecott Tunnel; the first tunnel to connect Contra Costa and Alameda Counties); Broadway Low Level Tunnel (first two bores), at today's level, opened in 1937; Third Bore (opened in 1962) including the accident and fire in the bore in 1982; and the opening of the Fourth Bore in 2013.
The two bores that opened in 1937 changed Contra Costa County from an area of small rural communities into one of growing suburbs.