406. WATER QUALITY – CONTAMINATION

406 WATER QUALITY ─ CONTAMINATION 406.1 A swimming pool, spa pool, or sauna shall be deemed contaminated when one (1) of the following conditions exists: (a) More than one (1) ten milliliter (10 ml) portion of a sample shows a positive test for coliform organisms when multi-tube fermentation technique is used; or more than one (1) coliform per fifty milliliters (50 ml) when the membrane filter test is used; or (b) Two (2) consecutive samples show a positive test for coliform organisms in any ten milliliter (10 ml) portion of a sample when the multi-tube fermentation technique is used or more than one (1) coliform per fifty milliliters (50 ml) when the membrane filter test is used; or (c) Two (2) of any ten (10) consecutive samples show a positive test for coliform organisms in any of the ten milliliter (10 ml) portions of a sample when the multi-tube fermentation technique is used or more than one (1) coliform per fifty milliliters (50 ml) when the membrane filter test is used; or (d) When performing diarrheal/Cryptosporidium decontamination in aquatic venues, the maximum allowable cyanuric acid concentration shall be 15 ppm. SOURCE: Final Rulemaking published at 64 DCR 5359 (June 9, 2017). District of Columbia Municipal Regulations Aquatic Facilities Regulations: Swimming Pools, Spa Pools, And Saunas 25-C DCMR § 406