Okla. Stat. tit. 11, § 11-37-209: District sewer or water lines without petition -

Preliminary plans and costs.

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.