Public Utilities Code § 150202

The retail transactions and use tax ordinance shall state the nature of the tax to be imposed, the tax rate or the maximum tax rate, the purposes for which the revenue derived from the tax will be used, and may set a term, not to exceed 15 years, during which the tax will be imposed. The purposes for which the tax revenues will be used may include, but are not limited to, the administration of this division, including legal actions related thereto, the construction, capital acquisition, maintenance, and operation of streets, roads, and highways, including state highways. These purposes include expenditures for the planning, environmental reviews, engineering and design costs, and related right-of-way acquisition. The ordinance shall reference an expenditure plan which shall include the allocation of revenues for the purposes authorized by this section.