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

Illinois American Water Company

Sewerage Systems, Mokena, Illinois. NPDES permit IL0032778, in force until Apr 30, 2031. Last 12 months: over a limit once (last June 2026). Source: EPA ECHO, Oct 22, 2026.

Reports due
About 25 days after each period: outfall 001 form 0 monthly (23 values), outfall INF form L monthly (4 values)
Last report on file
August 2026
Oct 2024 – Sep 2025
1 value over a limit, 0 required values missing, 0 of 24 reports late

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

Period endingParameterReportedLimitOver by
June 2026Coliform, fecal general, daily maximum686.7 #/100mL≤ 400 #/100mL72%

Limits in force (38)

ParameterStatisticLimitMonthsOutfall
Oxygen, dissolved [DO]monthly average minimum≥ 6 mg/LJan, Feb, Aug, Sep, Oct, Nov, Dec001
Oxygen, dissolved [DO]minimum weekly average≥ 4.5 mg/LJan, Feb, Aug, Sep, Oct, Nov, Dec001
Oxygen, dissolved [DO]minimum weekly average≥ 6.25 mg/LMar–Jul001
Oxygen, dissolved [DO]daily minimum≥ 4 mg/LJan, Feb, Aug, Sep, Oct, Nov, Dec001
Oxygen, dissolved [DO]daily minimum≥ 5 mg/LMar–Jul001
pHminimum≥ 6 SUall year001
pHmaximum≤ 9 SUall year001
Solids, total suspendedmonthly average≤ 12 mg/Lall year001
Solids, total suspendeddaily maximum≤ 24 mg/Lall year001
Solids, total suspendedmonthly average≤ 400 lb/dall year001
Solids, total suspendeddaily maximum≤ 801 lb/dall year001
Nitrogen, ammonia total [as N]monthly average≤ 1.5 mg/LMar, Apr, May, Sep, Oct001
Nitrogen, ammonia total [as N]monthly average≤ .7 mg/LJun–Aug001
Nitrogen, ammonia total [as N]daily maximum≤ 3.6 mg/LMar, Apr, May, Sep, Oct001
Nitrogen, ammonia total [as N]daily maximum≤ 4.5 mg/LJun–Aug001
Nitrogen, ammonia total [as N]daily maximum≤ 3.2 mg/LJan, Feb, Nov, Dec001
Nitrogen, ammonia total [as N]monthly average≤ 50 lb/dMar, Apr, May, Sep, Oct001
Nitrogen, ammonia total [as N]monthly average≤ 43 lb/dJun–Aug001
Nitrogen, ammonia total [as N]daily maximum≤ 120 lb/dMar, Apr, May, Sep, Oct001
Nitrogen, ammonia total [as N]daily maximum≤ 150 lb/dJun–Aug001
Nitrogen, ammonia total [as N]daily maximum≤ 107 lb/dJan, Feb, Nov, Dec001
Nitrogen, ammonia total [as N]weekly average≤ 1.8 mg/LJun–Aug001
Nitrogen, ammonia total [as N]weekly average≤ 60 lb/dJun–Aug001
Phosphorus, total [as P]daily maximumreport only (mg/L)all year001
Chloride [as Cl]daily maximumreport only (mg/L)all year001
Flow, in conduit or thru treatment plantmonthly averagereport only (MGD)all year001
Flow, in conduit or thru treatment plantdaily maximumreport only (MGD)all year001
Chlorine, total residualdaily maximum≤ .05 mg/LMay–Oct001
Chlorine, total residualdaily maximum≤ .05 mg/LJan, Feb, Mar, Apr, Nov, Dec001
Coliform, fecal generaldaily maximum≤ 400 #/100mLMay–Oct001
BOD, carbonaceous [5 day, 20 C]monthly average≤ 10 mg/Lall year001
BOD, carbonaceous [5 day, 20 C]daily maximum≤ 20 mg/Lall year001
BOD, carbonaceous [5 day, 20 C]monthly average≤ 334 lb/dall year001
BOD, carbonaceous [5 day, 20 C]daily maximum≤ 667 lb/dall year001
BOD, 5-day, 20 deg. Cmonthly averagereport only (mg/L)all yearINF
Solids, total suspendedmonthly averagereport only (mg/L)all yearINF
Flow, in conduit or thru treatment plantmonthly averagereport only (MGD)all yearINF
Flow, in conduit or thru treatment plantdaily maximumreport only (MGD)all yearINF

How strict are these limits?

Cited limits by parameter: Illinois'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/IL0032778 · MCP: https://passage-data.com/mcp