California's 10th congressional district

It received national attention in 1996 when Democrat Ellen Tauscher defeated incumbent Republican Bill Baker in what was considered an upset.

Although much of the suburban Tri-Valley region was shifted to the 11th congressional district, the city of Livermore remained in the 10th at Tauscher's request (as a member of the U.S. House Committee on Energy and Commerce, she had some oversight responsibilities over the U.S. Department of Energy, and hence indirectly of Lawrence Livermore National Laboratory).

On June 26, 2009, Tauscher resigned her seat to be sworn in as Undersecretary of State for Arms Control and International Security.

[7][8][9] In the ensuing special election held on November 3, 2009, former Democratic Lieutenant Governor John Garamendi won the seat over Republican David Harmer 53.0% to 42.7%.

It also shares much of the northwestern portion of the old 19th district (Turlock, Riverbank, Oakdale, and the rest of northeastern Stanislaus County).

The northern border is partitioned by Grizzly Peak Blvd, Seaview Trail, Camino Pablo, Bear Creek Rd, San Pablo Creek, Bear Creek, Brianes Reservoir, Burlington Northern Santa Fe, Highway 4, Alhambra Ave, Pacheco Blvd, Grandview Ave, Central Ave, Imhoff Dr, Bares Ave, Mount Diablo Creek, Union Pacific, Contra Costa Canal, 4WD Rd, Bailey Rd, James Donlon Blvd, Cambridge Dr, Reseda Way, S Royal links Cir, Carpinteria Dr, Barmouth Dr, Hillcrest Ave, Highway 4, and Highway 160.

The western border is partitioned by Old River, Italian Slough, Western Farms Ranch Rd, Rankin Rd, Highway J14, Byron Hot Springs Rd, Camino Diablo, Kellogg Creek, Sellers Ave, Brentwood Blvd, Alloro Dr, Ghiggeri Dr, Emilio Dr, Guthrie Ln, Balfour Rd, Chestnut St, Byron Highway, Orwood Rd, Burlington Northern Santa Fe, Werner Dredger Cut, and Rock Slough.

The 10th district takes in the south sides of the cities of Antioch and Martinez, the cities of Concord, Brentwood, Oakley, Pleasant Hill, Clayton, Walnut Creek, Lafayette, Orinda, and San Ramon, the towns of Danville and Moraga, and the census-designated places Norris Canyon, Camino Tassajara, Blackhawk, Diablo, Alamo, Castle Hill, Saranap, Acalanes Ridge, San Miguel, North Gate, Shell Ridge, Contra Costa Centre, Reliez Valley, Alhambra Valley, Mountain View, Vine Hill, Pacheco, Clyde, Knightsen, and Bethel Island.

District borders, 2002-2012.