(a) Each year, if an authority determines that it has surplus revenue from transportation projects, it shall reduce tolls, spend the surplus revenue on other transportation projects in the counties of the authority in accordance with Subsection (b), or deposit the surplus revenue to the credit of the Texas Mobility Fund.
(b) Consistent with other law and commission rule, an authority may spend surplus revenue on other transportation projects by:
(1) constructing a transportation project located within the counties of the authority;
(2) assisting in the financing of a toll or toll-free transportation project of another governmental entity; or
(3) with the approval of the commission, constructing a toll or toll-free transportation project and, on completion of the project, transferring the project to another governmental entity if:
(A) the other governmental entity authorizes the authority to construct the project and agrees to assume all liability and responsibility for the maintenance and operation of the project on its transfer; and
(B) the project is constructed in compliance with all laws applicable to the governmental entity.