Cal. PUC § 1202.2

In apportioning the cost of maintenance of automatic grade-crossing protection constructed or altered after October 1, 1965 under Section 1202, as between the railroad or street railroad corporations and the public agencies affected, the commission shall divide such maintenance cost in the same proportion as the cost of constructing such automatic grade-crossing protection is divided. The liability of cities, counties and cities and counties to pay the share of maintenance costs assigned to such local agencies by the commission shall be limited to funds set aside for allocation to the commission pursuant to Section 1231.1. The railroad or street railroad corporations and the public agencies affected may agree on a different division of maintenance costs. If the public agency affected agrees to assume a greater proportion of the cost of maintenance than the apportionment of the cost of construction, the difference shall be paid by the public agency from funds other than the State Highway Fund or any other state fund.