SUFFOLK CO DPW — NPDES permit NY0021750: limits, due date and EPA's record

NPDES permit NY0021750 · Major POTW · effective, expires 2028-11-30 · EPA's file as of 2026-09-19

EPA's record, 2025-09-01 to 2026-08-31

Last period with anything received: 2026-07-31. Most often over: Coliform, total general (1).

Reporting

Reports are due about 28 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (56)

Outfall	Parameter	Statistic	Limit	Months
002	Temperature, water deg. fahrenheit	DAILY MX	report only	all year
002	pH	DAILY MN	>= 6 SU	all year
002	pH	DAILY MX	<= 9 SU	all year
002	Solids, total suspended	MO AVG	<= 30 mg/L	all year
002	Solids, total suspended	7 DA AVG	<= 45 mg/L	all year
002	Solids, total suspended	MO AVG	<= 290 lb/d	all year
002	Solids, total suspended	7 DA AVG	<= 430 lb/d	all year
002	Solids, total suspended	MO AVG	report only	all year
002	Solids, total suspended	MO AVG	report only	all year
002	Solids, settleable	DAILY MX	<= .3 mL/L	all year
002	Nitrogen, total [as N]	MO AVG	report only	all year
002	Nitrogen, total [as N]	MO AVG	report only	all year
002	Nitrogen, total [as N]	RE	report only	all year
002	Nitrogen, total [as N]	MO AVG	report only	all year
002	Nitrogen, total [as N]	MO AVG	report only	all year
002	Nitrogen, ammonia total [as N]	MO AVG	report only	all year
002	Nitrogen, ammonia total [as N]	MO AVG	report only	all year
002	Nitrogen, nitrite total [as N]	MO AVG	report only	all year
002	Nitrogen, nitrite total [as N]	MO AVG	report only	all year
002	Nitrogen, nitrate total [as N]	MO AVG	report only	all year
002	Nitrogen, nitrate total [as N]	MO AVG	report only	all year
002	Nitrogen, Kjeldahl, total [as N]	MO AVG	report only	all year
002	Nitrogen, Kjeldahl, total [as N]	MO AVG	report only	all year
002	Phosphorus, total [as P]	DAILY MX	report only	all year
002	Phosphorus, total [as P]	DAILY MX	report only (alert)	all year
002	Cyanide, total [as CN]	DAILY MX	<= .042 mg/L	all year
002	Copper, total [as Cu]	DAILY MX	<= .063 mg/L (alert)	all year
002	Total agg concentration #1	MO AVG	report only	all year
002	Total agg concentration #1	Agg Rol Av	<= 213 lb/d	all year
002	Phosphate, ortho [as P]	DAILY MX	report only	all year
002	Phosphate, ortho [as P]	DAILY MX	report only	all year
002	Flow, in conduit or thru treatment plant	MO AVG	<= 1.15 MGD	all year
002	Chlorine, total residual	DAILY MX	<= .198 mg/L	all year
002	Enterococci	30DA GEO	<= 35 #/100mL	all year
002	Enterococci	30DA GEO	report only	all year
002	Enterococci	DAILY MX	report only	all year
002	Enterococci	DAILY MX	report only	all year
002	Mercury, total [as Hg]	DAILY MX	<= 50 ng/L	all year
002	Mercury, total [as Hg]	DAILY MX	<= 50 ng/L	all year
002	Mercury, total [as Hg]	DAILY MX	report only	all year
002	Mercury, total [as Hg]	DAILY MX	report only	all year
002	Coliform, fecal general	30DA GEO	<= 200 #/100mL	all year
002	Coliform, fecal general	7 DA GEO	<= 400 #/100mL	all year
002	Coliform, total general	MO MED	<= 700 #/100mL	all year
002	BOD, carbonaceous [5 day, 20 C]	MO AVG	<= 25 mg/L	all year
002	BOD, carbonaceous [5 day, 20 C]	7 DA AVG	<= 40 mg/L	all year
002	BOD, carbonaceous [5 day, 20 C]	MO AVG	<= 240 lb/d	all year
002	BOD, carbonaceous [5 day, 20 C]	7 DA AVG	<= 380 lb/d	all year
002	BOD, carbonaceous [5 day, 20 C]	MO AVG	report only	all year
002	BOD, carbonaceous [5 day, 20 C]	MO AVG	report only	all year
002	Solids, suspended percent removal	MO AV MN	>= 85 %	all year
002	Carbonaceous oxygen demand, % removal	MO AV MN	>= 85 %	all year
002	48Hr Acute Mysidopsis Bahia	MAXIMUM	<= 5.83 tox acute (alert)	all year
002	TU 48Hr Acute Cyprinodon variegatus	MAXIMUM	<= 5.83 tox acute (alert)	all year
002	TU Static Renewal Chronic Cyprinodeon variegatus	MAXIMUM	<= 26.4 tox chronic (alert)	all year
002	TU Static Renewal 7-Day Chronic Americamysis bahia (formerly Mysidopsis bahia)	MAXIMUM	<= 26.4 tox chronic (alert)	all year