Del. Code tit. 16 § 1407
None of the powers granted by this chapter shall be exercised in the construction, improvement, maintenance, extension or operation of any project or projects which in whole or in part shall duplicate or compete with existing utilities, public or private, serving substantially the same purposes. The municipality or municipalities organizing such an authority may, in the resolution or ordinance signifying their intention so to do, or from time to time by subsequent resolution or ordinance, specify the project or projects to be undertaken by the said authority, and no other projects shall be undertaken by the said authority than those so specified. If the municipality or municipalities organizing an authority fail to specify the project or projects to be undertaken, then the authority shall be deemed to have all the powers granted by this chapter.
No municipality which shall have created an authority under this chapter shall thereafter create any other authority serving the whole or any part of the same area. No municipality which shall have joined with any other municipality or municipalities in the creation of any authority under this chapter shall thereafter create or join in the creation of any other authority unless such other municipality or municipalities shall consent thereto by ordinance or resolution after a general referendum.
16 Del. C. § 1407