Cal. Sts. & Hy. Code § 880
Where land not exceeding 300 feet in width intervenes between the right-of-way line of a state highway, either existing or to be constructed, and the mean high tide line of the Pacific Ocean, or bays or estuaries thereof, the land may be acquired as a part of the highway right-of-way acquisition.
Land heretofore or hereafter so acquired may, except when required, in whole or in part, for state highway widening or other state highway requirements, be transferred to the control of the State Park and Recreation Commission and, when so transferred, shall be dedicated in perpetuity for beach, park, and recreational purposes for the benefit and use of the public. However, where such land which is not necessary for state highway purposes is producing oil, gas, or other hydrocarbons, or is within a distance of 660 feet from a producing oil or gas well, then if by a majority vote of the State Park and Recreation Commission and the California Transportation Commission it is determined that the acquisition of an easement thereof is desirable, and if the portion thereof lying between the mean high tide line and the extreme high tide line is not occupied by any well and adequate well sites exist on the remainder of the property, then, in accordance with this section, an easement may be acquired upon and over the portion of such land lying between the mean high tide line and the extreme high tide line as a right-of-way for persons traveling on foot and on horseback and for fishermen and for bathers.
If such land is more valuable for commercial purposes than for recreational purposes by reason of its use or suitability for railroad rights-of-way, docks, wharves, or other shipping or industrial purposes, or is producing oil, gas, or other hydrocarbons, or is within a distance of 660 feet from a producing oil or gas well, or is being zoned by the proper public authority for important commercial development, it shall not be acquired for such park or recreational purposes.
Ca. Sts. and High. Code § 880