Cal. Streets and Highways Code § 891

(a) All city, county, regional, and other local agencies responsible for the development or operation of bikeways or roadways where bicycle travel is permitted shall utilize the minimum safety design criteria established pursuant to Section 890.6, except as provided in subdivision (b), and shall utilize the uniform specifications and symbols for signs, markers, and traffic control devices established pursuant to Section 890.8. (b) An agency may utilize minimum safety design criteria other than those established by Section 890.6 if all of the following conditions are met: (1) The alternative criteria have been reviewed and approved by a qualified engineer with consideration for the unique characteristics and features of the proposed bikeway and surrounding environs. (2) The alternative criteria, or the description of the project with reference to the alternative criteria, are adopted by resolution at a public meeting, after having provided proper notice of the public meeting and opportunity for public comment. (3) The alternative criteria adhere to guidelines established by a national association of public agency transportation officials.