La. Stat. tit. 33 § 3829
In the event the local and special assessments originally levied or the water rates originally provided are insufficient for any cause whatsoever, to pay the principal and interest, or the principal or interest, in any one year of the said waterwork certificates outstanding at their respective maturity dates, or to make timely payments in connection with any amortized promissory notes issued, then in such event the political subdivision issuing such waterworks certificates or amortized notes under the provisions of R.S. 33:3822 through 33:3835, through its governing authority, is hereby authorized, empowered and obligated by ordinance to levy and collect, at such time or times as may be necessary, additional local or special assessments on each lot or parcel of real estate in the political subdivision or area involved, on a front foot basis, sufficient in amount to pay in full the said principal and interest, or the principal or interest of such waterwork certificates at their respective maturity dates or the necessary payments in connection with any amortized promissory notes issued. The amounts assessed in such ordinance or ordinances shall be due and collectible immediately on its passage and if not paid within thirty days from the date of its adoption, the governing authority of the political subdivision shall proceed against the property for the collection of the amount of the additional local or special assessments so levied, plus interest thereon and 10% additional for attorney's fees. A certified copy of each ordinance providing for the levy and collection of such additional local or special assessments shall be filed with the clerk of court of the parish in which the political subdivision is located promptly upon its adoption, who shall forthwith record the same in the mortgage records of the parish, and when so filed and recorded shall operate as a lien and privilege against all the real estate therein assessed and shall prime all other liens except taxes, and prior recorded local or special assessments levied for streets, sewerage or waterworks improvements.
La. R.S. § 33:3829