CA Veh Code Section 21651

(a)

Whenever a highway has been divided into two or more roadways by means of intermittent barriers or by means of a dividing section of not less than two feet in width, either unpaved or delineated by curbs, double-parallel lines, or other markings on the roadway, it is unlawful to do either of the following:

(1)

To drive any vehicle over, upon, or across the dividing section.

(2)

To make any left, semicircular, or U-turn with the vehicle on the divided highway, except through an opening in the barrier designated and intended by public authorities for the use of vehicles or through a plainly marked opening in the dividing section.

(b)

It is unlawful to drive any vehicle upon a highway, except to the right of an intermittent barrier or a dividing section which separates two or more opposing lanes of traffic. Except as otherwise provided in subdivision (c), a violation of this subdivision is a misdemeanor.

(c)

Any willful violation of subdivision (b) which results in injury to, or death of, a person shall be punished by imprisonment pursuant to subdivision (h) of Section 1170 of the Penal Code, or imprisonment in a county jail for a period of not more than six months.