La. Stat. tit. 38 § 1625
Within thirty days after qualifying, the appraisers shall begin their duties. They may at any time call upon the attorney of the district for legal advice and information relating to their duties, and the chief engineer or one of his assistants shall accompany the appraisers at all times and render his opinion in writing when called upon. The appraisers shall proceed to view the premises and determine the value of all lands and other property, within or without the district or sub-district, to be acquired and used for rights of way, canals, levees, holding basins, pumping plant sites, or other works set out in the plan for reclamation. They shall assess the amount of benefits, and the amount of damages, if any, that will accrue to each forty acre tract, or other smaller sub-division of land according to ownership as shown by the engineer's maps, railroads, and other rights of way, railroad roadways, and other property within district or sub-district, from the carrying out and putting into effect of the plan for reclamation theretofore adopted. The appraisers in assessing the benefits to lands, railroads, and other rights of way, railroad roadways, and other property not traversed by the works and improvements as provided for in the plan for reclamation, shall not consider what benefits will be derived by the property after other ditches, improvements, or other plans for reclamation shall have been constructed, but they shall assess only the benefits which will be or have been derived from the construction of the works and improvements set out in the plan for reclamation, or as they may afford an outlet for drainage or protection from overflow of the property. The appraisers shall give due consideration to any other drains, canals, ditches, levees, or systems of reclamation, which may have already been constructed and which afford partial or complete protection to any tract or parcel of land in the district or sub-district. Should any other drains, canals, ditches, levees, or systems of reclamation, have been constructed by a public agency through a system of taxation or assessment against the lands, then and in any event the appraisers shall give due credit to the lands for the improvements. Should, however, the other drains, canals, ditches, levees, or systems of reclamation, have been constructed by landowners, then, the appraisers shall appraise the value of the improvements constructed by the landowners, and incorporate the improvements in their report. The improvements shall be expropriated by the drainage district, in the manner provided in R.S. 38:1626, and the landowners shall be reimbursed the value thereof. The railroad and other rights of way, railroad, and other property shall be assessed according to the increased physical efficiency and decreased maintenance cost of roadways by reason of the protection to be derived from the proposed works and improvements. The appraisers may not change the plan for reclamation theretofore provided for.
In assessing benefits, all lands enjoying a servitude of natural drainage shall be entitled to continue to receive equivalent artificial drainage without charge therefor and without having the drainage considered as an element in assessing benefits against the lands.
La. R.S. § 38:1625