The board of county commissioners for any unincorporated portion of the county, upon application by any individual, organization, or agency of private enterprise, may grant permission by resolution to such individual, organization, or agency to construct water or sewer lines, or both, under the supervision of the board. Such resolution, and any contract entered into pursuant to such resolution, shall authorize the collection of prorated shares of the cost of such improvement as provided in this section.

The board shall collect and return to such individual, organization, or agency a prorated share of the cost of such improvement in any instance in which such improvement is tapped into by a nonparticipant in the original cost. The prorated share shall be based on the front footage of improvement to the nonparticipant and shall not be in excess of the amount chargeable to such nonparticipant if such nonparticipant had participated in the aforesaid improvements.

No subsequent assignee or grantee of such individual, organization, or agency shall be considered a nonparticipant in the original cost.

A copy of the resolution granting permission to construct water or sewer lines and authorizing the collection of a prorated share shall be filed by the applicant with the county auditor, who shall keep an index by location of all such resolutions. The filing of such resolution constitutes constructive notice thereof. The county auditor shall charge a fee of one dollar for each resolution filed. No nonparticipant shall be required to pay the prorated share of the cost of such improvement permitted by a resolution adopted after the effective date of this section without such notice.

The county commissioners may make such rules and regulations as may be necessary to administer this section.