Local Government Code §372.015

(a) The governing body of the municipality or county shall apportion the cost of an improvement to be assessed against property in an improvement district. The apportionment shall be made on the basis of special benefits accruing to the property because of the improvement. (b) Cost of an improvement may be assessed: (1) equally per front foot or square foot; (2) according to the value of the property as determined by the governing body, with or without regard to improvements on the property; or (3) in any other manner that results in imposing equal shares of the cost on property similarly benefitted. (c) The governing body may establish by ordinance or order: (1) reasonable classifications and formulas for the apportionment of the cost between the municipality or county and the area to be assessed; and (2) the methods of assessing the special benefits for various classes of improvements. (d) The amount of assessment for each property owner may be adjusted following the annual review of the service plan.