EPA Letter approving ADEQ's Draft 303d List of Impaired Waterbodies, including Big Creek and adjacent sections of the Buffalo River. May 15, 2020.
ADEQ's Final 303(d) documents, posted April 6, 2016. See the Letter of Responsiveness for responses to public comments and the 305(b) Integrated Report for details on impaired streams. Big Creek was included in Category 3 for Phosphorus and Nitrogen. Category 3 means there is insufficient data to determine impairment.
EPA Letter approving ADEQ's 303(d) list for the periods 2008-2016. July 19, 2017 In spite of data showing elevated E. coli and low dissolved oxygen levels in Big Creek, and concerns expressed by NPS, USGS and many private citizens, EPA approved ADEQ's determination that Big Creek was not impaired because there was insufficient data.