California Code, Public Utilities Code - PUC § 102284

(a) The district may enter into agreements for the joint use of any property and rights by the district and any public agency or public utility operating transit facilities; may enter into agreements with any public agency or public utility operating any transit facilities, and wholly or partially within or without the district, for the joint use of any property of the district or of the public agency or public utility, or the establishment of through routes, joint fares, transfer of passengers or pooling arrangements.

(b) In addition to any power described in subdivision (a), the district may enter into agreements for the joint use or joint development of any property or rights by the district and any public agency, or public utility operating transit facilities or nontransit facilities, or both, or any other person, firm, corporation, association, organization, or other entity, public or private, either, in whole or in part, within or outside the district, for the joint use or development of any nontransit facilities of the district or of the public agency, public utility, person, firm, corporation, association, organization, or other entity, public or private, for the establishment of through routes, joint fares, transfer of passengers, pooling arrangements, station cost-sharing, connector fees, or land, air, or development rights, sales or leasing, necessary for, incidental to, or convenient for, the full exercise of the powers granted in this chapter. For the purpose of this section, the following terms have the following meanings:

(c) Construction projects or works of improvement for facilities authorized by the district under the terms of a joint development agreement that is approved under the authority conferred by this section shall be considered a public works project subject to Chapter 1 (commencing with Section 1720) of Part 7 of Division 2 of the Labor Code and shall be enforced by the Department of Industrial Relations in the same manner in which it carries out this responsibility under the Labor Code.