Cal. Sts. & Hy. Code § 678
Except as otherwise provided in this section, such a bond shall not be required of any county, city, public corporation or political subdivision which is authorized by law to establish or maintain any works or facilities in, under or over any public highway, nor shall the application of any such governmental unit for a permit be denied. Every such applicant is entitled as a matter of right to a permit, but is otherwise subject to the provisions of this article and to all reasonable conditions and provisions made by the department in any such permit.
The department may require of any such applicant a bond in a sum not to exceed twenty thousand dollars, if such applicant has in fact prior to such application failed to comply with the provisions of this article or with the provisions of a previous permit.
Ca. Sts. and High. Code § 678