Passage Data · Check a report · Use it from your AI

Hilton Head Public Service District

Sewage treatment plant, major discharger, Hilton Head, Sc 29925, South Carolina. NPDES permit SC0046191 expired Dec 31, 2025; its limits still apply. Last 12 months: over a limit 6 times (last May 2026). Source: EPA ECHO, Oct 22, 2026.

Reports due
About 29 days after each period: outfall 001 form 1 monthly (33 values), outfall 001 form 2 quarterly (4 values), outfall 002 form 1 monthly (4 values), outfall 003 form 1 monthly (4 values), outfall 004 form 1 monthly (4 values), outfall 005 form 1 monthly (4 values), and 2 more forms
Last report on file
September 2026
Oct 2024 – Sep 2025
5 values over a limit, 0 required values missing, 0 of 77 reports late

Last 12 months (Oct 1, 2025 – Sep 30, 2026)

Period endingParameterReportedLimitOver by
January 2026Solids, total suspended, weekly average9.2≤ 7.5 mg/L23%
January 2026Zinc, total [as Zn], daily maximum.104≤ .095 mg/L9%
February 2026Zinc, total [as Zn], daily maximum.261≤ .095 mg/L175%
February 2026Zinc, total [as Zn], daily maximum5.2≤ 5.1 lb/d2%
February 2026Zinc, total [as Zn], monthly average.129≤ .086 mg/L50%
May 2026Coliform, fecal general, daily maximum47.9≤ 43 MPN/100mL11%

Limits in force (61)

ParameterStatisticLimitMonthsOutfall
Oxygen, dissolved [DO]minimum≥ 5 mg/Lall year001
BOD, 5-day, 20 deg. Cmonthly average≤ 5 mg/Lall year001
BOD, 5-day, 20 deg. Cweekly average≤ 7.5 mg/Lall year001
BOD, 5-day, 20 deg. Cmonthly average≤ 270 lb/dall year001
BOD, 5-day, 20 deg. Cweekly average≤ 401 lb/dall year001
pHminimum≥ 6 SUall year001
pHmaximum≤ 8.5 SUall year001
Solids, total suspendedmonthly average≤ 5 mg/Lall year001
Solids, total suspendedweekly average≤ 7.5 mg/Lall year001
Solids, total suspendedmonthly average≤ 270 lb/dall year001
Solids, total suspendedweekly average≤ 401 lb/dall year001
Nitrogen, ammonia total [as N]monthly average≤ 5 mg/LMar–Oct001
Nitrogen, ammonia total [as N]weekly average≤ 7.5 mg/LMar–Oct001
Nitrogen, ammonia total [as N]monthly average≤ 270 lb/dMar–Oct001
Nitrogen, ammonia total [as N]weekly average≤ 401 lb/dMar–Oct001
Hardness, total [as CaCO3]monthly averagereport only (mg/L)all year001
Hardness, total [as CaCO3]daily maximumreport only (mg/L)all year001
Zinc, total [as Zn]monthly average≤ .086 mg/Lall year001
Zinc, total [as Zn]daily maximum≤ .095 mg/Lall year001
Zinc, total [as Zn]monthly average≤ 4.6 lb/dall year001
Zinc, total [as Zn]daily maximum≤ 5.1 lb/dall year001
Flow, in conduit or thru treatment plantmonthly averagereport only (MGD)all year001
Flow, in conduit or thru treatment plantweekly averagereport only (MGD)all year001
Cyanide, free availablemonthly average≤ .001 mg/Lall year001
Cyanide, free availabledaily maximum≤ .001 mg/Lall year001
Cyanide, free availablemonthly average≤ .053 lb/dall year001
Cyanide, free availabledaily maximum≤ .053 lb/dall year001
Enterococci30-day geometric mean≤ 35 MPN/100mLall year001
Enterococcidaily maximum≤ 104 MPN/100mLall year001
Enterococci30-day geometric mean≤ 35 MPN/100mLall year001
Enterococcidaily maximum≤ 800 MPN/100mLall year001
Coliform, fecal general30-day geometric mean≤ 14 MPN/100mLall year001
Coliform, fecal generaldaily maximum≤ 43 MPN/100mLall year001
Coliform, fecal general30-day geometric mean≤ 14 MPN/100mLall year001
Coliform, fecal generaldaily maximum≤ 200 MPN/100mLall year001
BOD, 5-day, percent removalmonthly average minimum≥ 85 %all year001
Solids, suspended percent removalmonthly average minimum≥ 85 %all year001
LC50 Static 48Hr Acute Ceriodaphnia dubiadaily minimumreport only (%)all year001
%Effect Static Renewal 7 Day Chronic Ceriodaphnia dubiamonthly average≤ 25 %all year001
%Effect Static Renewal 7 Day Chronic Ceriodaphnia dubiadaily maximum≤ 40 %all year001
IC25 Static Renewal 7 Day Chronic Ceriodaphnia dubiadaily minimumreport only (%)all year001
Flow, in conduit or thru treatment plantmonthly average≤ .7 MGDall year002
Flow, in conduit or thru treatment plantweekly average≤ .7 MGDall year002
Chlorine, total residualmonthly average≤ .008 mg/Lall year002
Chlorine, total residualdaily maximum≤ .013 mg/Lall year002
Flow, in conduit or thru treatment plantmonthly average≤ 1.39 MGDall year003
Flow, in conduit or thru treatment plantweekly average≤ 1.39 MGDall year003
Chlorine, total residualmonthly average≤ .008 mg/Lall year003
Chlorine, total residualdaily maximum≤ .013 mg/Lall year003
Flow, in conduit or thru treatment plantmonthly average≤ 1.68 MGDall year004
Flow, in conduit or thru treatment plantweekly average≤ 1.68 MGDall year004
Chlorine, total residualmonthly average≤ .008 mg/Lall year004
Chlorine, total residualdaily maximum≤ .013 mg/Lall year004
Flow, in conduit or thru treatment plantmonthly average≤ .9 MGDall year005
Flow, in conduit or thru treatment plantweekly average≤ .9 MGDall year005
Chlorine, total residualmonthly average≤ .008 mg/Lall year005
Chlorine, total residualdaily maximum≤ .013 mg/Lall year005
Flow, in conduit or thru treatment plantmonthly average≤ 1.423 MGDall year006
Flow, in conduit or thru treatment plantdaily maximum≤ 1.423 MGDall year006
Chlorine, total residualmonthly average≤ .008 mg/Lall year006
Chlorine, total residualdaily maximum≤ .013 mg/Lall year006

How strict are these limits?

Cited limits by parameter: South Carolina's rules and the federal ones.

Check this month's numbers Email me before each report is due

· Save this facility as a site · Superfund sites nearby · Your permits on one board

On EPA ECHO: Facility report · DMR history

Your permit document is the final word. As JSON: /api/v1/permits/SC0046191 · MCP: https://passage-data.com/mcp