Missouri-American Water Company — NPDES permit MO0097411: limits, due date and EPA's record

Sewerage Systems, Jefferson City, Missouri. NPDES permit MO0097411 expired Jun 30, 2025; its limits still apply. Last 12 months: over a limit once (last June 2026). Source: EPA ECHO, Oct 22, 2026.

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

Period ending	Parameter	Reported	Limit	Over by
June 2026	BOD, 5-day, 20 deg. C, weekly average	52	≤ 45 mg/L	16%

Limits in force (22)

Parameter	Statistic	Limit	Months
Oxygen, dissolved [DO]	daily minimum	report only (mg/L)	Apr–Dec
Oxygen, dissolved [DO]	monthly average minimum	report only (mg/L)	Apr–Dec
BOD, 5-day, 20 deg. C	weekly average	≤ 45 mg/L	all year
BOD, 5-day, 20 deg. C	monthly average	≤ 30 mg/L	all year
pH	daily minimum	≥ 6.5 SU	all year
pH	daily maximum	≤ 9 SU	all year
Solids, total suspended	weekly average	≤ 45 mg/L	all year
Solids, total suspended	monthly average	≤ 30 mg/L	all year
Nitrogen, ammonia total [as N]	daily maximum	≤ 8.4 mg/L	Jul–Sep
Nitrogen, ammonia total [as N]	daily maximum	≤ 12.1 mg/L	Jan–Mar
Nitrogen, ammonia total [as N]	daily maximum	≤ 10.1 mg/L	Apr–Jun
Nitrogen, ammonia total [as N]	daily maximum	≤ 8.4 mg/L	Oct–Dec
Nitrogen, ammonia total [as N]	monthly average	≤ 1 mg/L	Jul–Sep
Nitrogen, ammonia total [as N]	monthly average	≤ 3.1 mg/L	Jan–Mar
Nitrogen, ammonia total [as N]	monthly average	≤ 1.5 mg/L	Apr–Jun
Nitrogen, ammonia total [as N]	monthly average	≤ 2.2 mg/L	Oct–Dec
Flow, in conduit or thru treatment plant	daily maximum	report only (MGD)	all year
Flow, in conduit or thru treatment plant	monthly average	report only (MGD)	all year
Chlorine, total residual	daily maximum	≤ 18 ug/L	Apr–Dec
Chlorine, total residual	monthly average	≤ 9 ug/L	Apr–Dec
E. coli	daily maximum	≤ 1030 #/100mL	Apr–Dec
E. coli	30-day geometric mean	≤ 206 #/100mL	Apr–Dec

How strict are these limits?

Your permit document is the final word. As JSON: /api/v1/permits/MO0097411 · MCP: https://passage-data.com/mcp