Whenever the governing body deems district sewers or district water distribution lines necessary, it may proceed with such work without petition, and shall require, by resolution, the municipal engineer, or other registered professional engineer, to prepare and file preliminary plans, showing a preliminary estimate of the cost of such improvement, and an assessment plat showing the area to be assessed. In the event noncontiguous areas are included in the same district, separate preliminary estimates shall be filed as to each area. The governing body may adopt any material or methods for the construction of such work.
Okla. Stat. tit. 11, § 37-209