Section 32. Execution of authorized public works and improvements.— All repair or construction of any work or public improvements, except parks, boulevards, streets or alleys, involving an estimated cost of three thousand pesos or more shall be awarded by the Mayor upon the recommendation of the city engineer to the lowest responsible bidder after public advertisement by posting notices of the call for bids in conspicuous places in the City Hall and other public places, which shall not be less than ten, and by publication in the Official Gazette, both for not less than ten days: Provided, However, That the city engineer may, with the approval of the President of the Philippines, upon the recommendation of the Secretary of Public Works and Communications, execute by administration any such public work costing three thousand pesos or more.

In case of public works involving an expenditure of less than three thousand pesos, it shall be discretionary with the city engineer either to proceed with the work himself or to let the contract to the lowest bidder after such publication and notice as shall be deemed appropriate or as may be, by regulations, prescribed.