Any area situated in any unincorporated part of one or more contiguous counties or in one or more municipal corporations, or both, may be organized as a regional water and sewer district in the manner and subject to the conditions provided in Chapter 6119. of the Revised Code, for either or both of the following purposes:

1. (A) To supply water to users within and without the district;
2. (B) To provide for the collection, treatment, and disposal of waste water within and without the district.