To the end that the Authority shall not unduly compete with the existing publicly operated water systems in the county, the Authority shall not sell water to be used by persons or private corporations within the corporate limits of municipalities which own and operate therein a municipal waterworks system or areas now served by such municipalities without the consent of the municipal officers of such municipalities, nor shall it sell water elsewhere than in Edgefield County and in a small area in the southwestern corner of Aiken County bounded on the cast by the eastern right of way of U.S. Highway No. 25 and on the south by the southern right of way of U.S. Interstate 20. Edgefield County and the above described area of Aiken County are hereby defined to be the service area of the Authority.