California Code, Elections Code - ELEC § 15260

(a) The elections official of the jurisdiction shall establish one or more election return centers for the purpose of facilitating the compilation of election returns and expediting their announcement to the public.

(b) In establishing a return center, the elections official may designate a group of precincts which the center shall serve and this designation shall be available for public inspection no later than 15 days before the election. The election return center may be at any public place as the elections official designates.