La. Stat. tit. 33 § 4160.14
Any municipality or parish proceeding under the authority of this Chapter may participate in the payment of the total cost of any project authorized hereunder, in such a manner and to such extent that the governing authority of the municipality or parish may determine, provided that any funds so used by the municipality or parish shall be in such amounts as it may have available for such purpose and from sources other than the imposition of special assessments. Such participation by the municipality or parish may be allocated to any one or more projects as the governing authority of the municipality or parish may determine, and the amount of the municipality's or parish participation shall be deducted from the total cost of the improvements for the purpose of levying local or special assessments hereunder.
La. R.S. § 33:4160.14