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

City of Mount Ayr

Sewage treatment plant, Mount Ayr, Iowa. NPDES permit IA0023574, in force until Apr 30, 2029. Last 12 months: over a limit 5 times (last May 2026), 2 of 11 reports late. Source: EPA ECHO, Oct 22, 2026.

Reports due
About 15 days after each period: form A monthly (30 values)
Last report on file
August 2026
Oct 2024 – Sep 2025
3 values over a limit, 0 required values missing, 0 of 12 reports late

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

Period endingParameterReportedLimitOver by
November 2025Solids, total suspended, 30-day average50≤ 30 mg/L67%
November 2025Solids, total suspended, 7-day average192≤ 45 mg/L327%
May 2026Solids, total suspended, 30-day average392.3615≤ 195 lb/d101%
May 2026Solids, total suspended, 7-day average1553.391≤ 293 lb/d430%
May 2026Solids, total suspended, 7-day average74≤ 45 mg/L64%

Limits in force (74)

ParameterStatisticLimitMonths
Oxygen, dissolved [DO]daily minimum≥ 5 mg/Lall year
BOD, 5-day, 20 deg. C30-day averagereport only (mg/L)all year
BOD, 5-day, 20 deg. Cdaily maximumreport only (mg/L)all year
BOD, 5-day, 20 deg. C30-day averagereport only (lb/d)all year
BOD, 5-day, 20 deg. Cdaily maximumreport only (lb/d)all year
pHdaily minimum≥ 6.5 SUall year
pHdaily maximum≤ 9 SUall year
pH30-day averagereport only (SU)all year
pHdaily maximumreport only (SU)all year
Solids, total suspended30-day average≤ 30 mg/Lall year
Solids, total suspended7-day average≤ 45 mg/Lall year
Solids, total suspended30-day average≤ 195 lb/dall year
Solids, total suspended7-day average≤ 293 lb/dall year
Solids, total suspended30-day averagereport only (mg/L)all year
Solids, total suspendeddaily maximumreport only (mg/L)all year
Solids, total suspended30-day averagereport only (lb/d)all year
Solids, total suspendeddaily maximumreport only (lb/d)all year
Nitrogen, ammonia total [as N]30-day average≤ 1 mg/LAug
Nitrogen, ammonia total [as N]30-day average≤ 1.1 mg/LSep
Nitrogen, ammonia total [as N]30-day average≤ 2.5 mg/LDec
Nitrogen, ammonia total [as N]30-day average≤ 1.6 mg/LOct
Nitrogen, ammonia total [as N]30-day average≤ 1 mg/LJul
Nitrogen, ammonia total [as N]30-day average≤ 2.3 mg/LNov
Nitrogen, ammonia total [as N]30-day average≤ 1.5 mg/LApr
Nitrogen, ammonia total [as N]30-day average≤ 4 mg/LFeb
Nitrogen, ammonia total [as N]30-day average≤ 1.7 mg/LMay
Nitrogen, ammonia total [as N]30-day average≤ 3.4 mg/LJan
Nitrogen, ammonia total [as N]30-day average≤ 1.3 mg/LJun
Nitrogen, ammonia total [as N]30-day average≤ 3.4 mg/LMar
Nitrogen, ammonia total [as N]daily maximum≤ 16.2 mg/LAug
Nitrogen, ammonia total [as N]daily maximum≤ 16.5 mg/LSep
Nitrogen, ammonia total [as N]daily maximum≤ 16 mg/LDec
Nitrogen, ammonia total [as N]daily maximum≤ 15.7 mg/LOct
Nitrogen, ammonia total [as N]daily maximum≤ 17.6 mg/LJul
Nitrogen, ammonia total [as N]daily maximum≤ 14.7 mg/LNov
Nitrogen, ammonia total [as N]daily maximum≤ 15.7 mg/LApr
Nitrogen, ammonia total [as N]daily maximum≤ 14.2 mg/LFeb
Nitrogen, ammonia total [as N]daily maximum≤ 15.2 mg/LMay
Nitrogen, ammonia total [as N]daily maximum≤ 15.2 mg/LJan
Nitrogen, ammonia total [as N]daily maximum≤ 14.4 mg/LJun
Nitrogen, ammonia total [as N]daily maximum≤ 14.7 mg/LMar
Nitrogen, ammonia total [as N]30-day average≤ 6.2 lb/dAug
Nitrogen, ammonia total [as N]30-day average≤ 6.9 lb/dSep
Nitrogen, ammonia total [as N]30-day average≤ 16.1 lb/dDec
Nitrogen, ammonia total [as N]30-day average≤ 10.1 lb/dOct
Nitrogen, ammonia total [as N]30-day average≤ 6.5 lb/dJul
Nitrogen, ammonia total [as N]30-day average≤ 15.1 lb/dNov
Nitrogen, ammonia total [as N]30-day average≤ 9.9 lb/dApr
Nitrogen, ammonia total [as N]30-day average≤ 25.7 lb/dFeb
Nitrogen, ammonia total [as N]30-day average≤ 11.3 lb/dMay
Nitrogen, ammonia total [as N]30-day average≤ 22.2 lb/dJan
Nitrogen, ammonia total [as N]30-day average≤ 8.5 lb/dJun
Nitrogen, ammonia total [as N]30-day average≤ 22.2 lb/dMar
Nitrogen, ammonia total [as N]daily maximum≤ 105.5 lb/dAug
Nitrogen, ammonia total [as N]daily maximum≤ 107.3 lb/dSep
Nitrogen, ammonia total [as N]daily maximum≤ 103.8 lb/dDec
Nitrogen, ammonia total [as N]daily maximum≤ 102.1 lb/dOct
Nitrogen, ammonia total [as N]daily maximum≤ 114.4 lb/dJul
Nitrogen, ammonia total [as N]daily maximum≤ 95.5 lb/dNov
Nitrogen, ammonia total [as N]daily maximum≤ 102.1 lb/dApr
Nitrogen, ammonia total [as N]daily maximum≤ 92.4 lb/dFeb
Nitrogen, ammonia total [as N]daily maximum≤ 98.8 lb/dMay
Nitrogen, ammonia total [as N]daily maximum≤ 98.8 lb/dJan
Nitrogen, ammonia total [as N]daily maximum≤ 93.9 lb/dJun
Nitrogen, ammonia total [as N]daily maximum≤ 95.5 lb/dMar
Nitrogen, Kjeldahl, total [as N]30-day averagereport only (mg/L)all year
Nitrogen, Kjeldahl, total [as N]daily maximumreport only (mg/L)all year
Nitrogen, Kjeldahl, total [as N]30-day averagereport only (lb/d)all year
Nitrogen, Kjeldahl, total [as N]daily maximumreport only (lb/d)all year
E. coligeometric mean≤ 630 #/100mLMar–Nov
BOD, carbonaceous [5 day, 20 C]30-day average≤ 25 mg/Lall year
BOD, carbonaceous [5 day, 20 C]7-day average≤ 40 mg/Lall year
BOD, carbonaceous [5 day, 20 C]30-day average≤ 163 lb/dall year
BOD, carbonaceous [5 day, 20 C]7-day average≤ 260 lb/dall year

How strict are these limits?

Cited limits by parameter: Iowa'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/IA0023574 · MCP: https://passage-data.com/mcp