The following actions of the Austin Utilities Board, Park and Recreation Board, and Library Board shall be effective only if confirmed by the enactment of an ordinance of the city council:
(a) any action which reasonably can be expected to require the direct or indirect expenditure of moneys in the city treasury or any separate fund maintained by any such board during any one year period in an amount greater than 20 percent of the annual city budget for the fiscal year in which such action is taken.
(b) any action which legally obligates the City of Austin, under contract or otherwise, for a period greater than five years.
Any ordinance enacted by the council confirming action of the type set forth in this section shall be subject to the referendum process provided for in Section 2.07 of the City Charter.