La. Stat. tit. 33 § 3992
The governing authority of any sewerage district taking advantage of the provisions of this Sub-part, shall upon the completion of any contract awarded as provided for herein, provide for the final inspection of the work performed thereunder and the improvements made, and if the work be found to have been completed satisfactorily in accordance with said contract, as evidenced by a certificate of the project engineer, the said governing authority shall by ordinance duly adopted approve and accept the said work and fulfill its obligations under the said contract after compliance with the laws of Louisiana relative to the completion of contracts involving public works, by full payment therefor of any and all amounts and balances due the said contractor, including all retained percentages of payments previously made thereon on engineer's estimates, and which percentages were retained pending the completion of the said work.
La. R.S. § 33:3992