JUSTICE O?CONNOR delivered the opinion of the Court.
Petitioner South Florida Water Management District operates a pumping facility that transfers water from a
canal into a reservoir a short distance away. Respondents Miccosukee Tribe of Indians and the Friends of the Everglades brought a citizen suit under the Clean Water Act contending that the pumping facility is required to obtain a discharge permit under the National Pollutant Discharge Elimination System. The District Court agreed and granted summary judgment to respondents. A panel of the United States Court of Appeals for the Eleventh Circuit affirmed. Both the District Court and the Eleventh Circuit rested their holdings on the predicate determination that the canal and reservoir are two distinct water bodies. For the reasons explained below, we vacate and remand for further development of the factual record as to the accuracy of that determination.
…..We find that further development of the record is necessary to resolve the dispute over the validity of the distinction between (the two water bodies) C?11 and WCA?3. After reviewing the full record, it is possible that the District Court will conclude that C?11 and WCA?3 are not meaningfully distinct water bodies. If it does so, then the S?9 pump station will not need an NPDES permit. In addition, the Government?s broader ?unitary waters? argument is open to the District on remand. Accordingly, the judgment of the United States Court of Appeals for the Eleventh Circuit is vacated, and the case is remanded for further proceedings consistent with this opinion.