74:51:01:51Criteria

for limited contact recreation waters. The criteria of parameters for limited contact recreation waters and their allowable variations that are not included under § 74:51:01:55 and Appendix B, unless set under § 74:51:01:24, are as found in the following table and only apply May 1 - September 30: Parameter Criteria Unit of Measure Special Conditions Dissolved oxygen as measured anywhere in the water column of a non-stratified water body, or in the epilimnion and metalimnion of a stratified water body > 5.0 mg/L daily minimum Escherichia coli < 630 /100mL geometric mean based on a minimum of 5 samples obtained during separate 24-hour periods for any 30-day period < 1178 in any one sample Microcystin 8 µg/L Not to be exceeded in more than three 10-day assessment periods over the course of the recreation season Cylindrospermopsin 15 µg/L

Source: SL 1975, ch 16, § 1; 4 SDR 32, effective December 4, 1977; transferred from § 34:04:02:41, effective July 1, 1979; 10 SDR 145, effective July 4, 1984; 13 SDR 129, 13 SDR 141, effective July 1, 1987; 19 SDR 111, effective January 31, 1993; transferred from § 74:03:02:41, July 1, 1996; 24 SDR 10, effective July 20, 1997; 35 SDR 253, effective May 12, 2009; 42 SDR 103, effective January 19, 2016; 47 SDR 110, effective April 27, 2021.