City of Cedar Falls — NPDES permit IA0036633: limits, due date and EPA's record

Sewage treatment plant, major discharger, Cedar Falls, Iowa. NPDES permit IA0036633, in force until Dec 31, 2029. Last 12 months: no values over a limit. Source: EPA ECHO, Oct 22, 2026.

Limits in force (146)

Parameter	Statistic	Limit	Months	Outfall
BOD, 5-day, 20 deg. C	30-day average	report only (mg/L)	all year	001
BOD, 5-day, 20 deg. C	daily maximum	report only (mg/L)	all year	001
BOD, 5-day, 20 deg. C	30-day average	report only (lb/d)	all year	001
BOD, 5-day, 20 deg. C	daily maximum	report only (lb/d)	all year	001
pH	daily minimum	≥ 6 SU	all year	001
pH	daily maximum	≤ 9 SU	all year	001
pH	30-day average	report only (SU)	all year	001
pH	daily maximum	report only (SU)	all year	001
Solids, total suspended	30-day average	≤ 30 mg/L	all year	001
Solids, total suspended	7-day average	≤ 45 mg/L	all year	001
Solids, total suspended	30-day average	≤ 2202 lb/d	all year	001
Solids, total suspended	7-day average	≤ 3303 lb/d	all year	001
Solids, total suspended	30-day average	report only (mg/L)	all year	001
Solids, total suspended	daily maximum	report only (mg/L)	all year	001
Solids, total suspended	30-day average	report only (lb/d)	all year	001
Solids, total suspended	daily maximum	report only (lb/d)	all year	001
Nitrogen, total [as N]	30-day average	≤ 1303.4 lb/d	all year	001
Nitrogen, total [as N]	daily maximum	≤ 2133.5 lb/d	all year	001
Nitrogen, total [as N]	30-day average	report only (mg/L)	all year	001
Nitrogen, total [as N]	daily maximum	report only (mg/L)	all year	001
Nitrogen, total [as N]	30-day average	report only (lb/d)	all year	001
Nitrogen, total [as N]	daily maximum	report only (lb/d)	all year	001
Nitrogen, ammonia total [as N]	30-day average	≤ 12.8 mg/L	Jul	001
Nitrogen, ammonia total [as N]	30-day average	≤ 31.6 mg/L	Dec	001
Nitrogen, ammonia total [as N]	30-day average	≤ 19.9 mg/L	Oct	001
Nitrogen, ammonia total [as N]	30-day average	≤ 29.8 mg/L	Nov	001
Nitrogen, ammonia total [as N]	30-day average	≤ 19.1 mg/L	May	001
Nitrogen, ammonia total [as N]	30-day average	≤ 50.1 mg/L	Feb	001
Nitrogen, ammonia total [as N]	30-day average	≤ 19.3 mg/L	Apr	001
Nitrogen, ammonia total [as N]	30-day average	≤ 25.7 mg/L	Mar	001
Nitrogen, ammonia total [as N]	30-day average	≤ 12.1 mg/L	Aug	001
Nitrogen, ammonia total [as N]	30-day average	≤ 43.8 mg/L	Jan	001
Nitrogen, ammonia total [as N]	30-day average	≤ 12.3 mg/L	Jun	001
Nitrogen, ammonia total [as N]	30-day average	≤ 13.4 mg/L	Sep	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 73.9 mg/L	Jul	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 62.3 mg/L	Dec	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 62 mg/L	Oct	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 60.5 mg/L	Nov	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 70.2 mg/L	May	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 92.6 mg/L	Feb	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 61.9 mg/L	Apr	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 79.7 mg/L	Mar	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 71.8 mg/L	Aug	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 81.3 mg/L	Jan	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 69.3 mg/L	Jun	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 63.2 mg/L	Sep	001
Nitrogen, ammonia total [as N]	30-day average	≤ 826.4 lb/d	Jul	001
Nitrogen, ammonia total [as N]	30-day average	≤ 2049.7 lb/d	Dec	001
Nitrogen, ammonia total [as N]	30-day average	≤ 1287.7 lb/d	Oct	001
Nitrogen, ammonia total [as N]	30-day average	≤ 1927.9 lb/d	Nov	001
Nitrogen, ammonia total [as N]	30-day average	≤ 1242 lb/d	May	001
Nitrogen, ammonia total [as N]	30-day average	≤ 3248.6 lb/d	Feb	001
Nitrogen, ammonia total [as N]	30-day average	≤ 1253.5 lb/d	Apr	001
Nitrogen, ammonia total [as N]	30-day average	≤ 1664.8 lb/d	Mar	001
Nitrogen, ammonia total [as N]	30-day average	≤ 784.1 lb/d	Aug	001
Nitrogen, ammonia total [as N]	30-day average	≤ 2836.9 lb/d	Jan	001
Nitrogen, ammonia total [as N]	30-day average	≤ 800.9 lb/d	Jun	001
Nitrogen, ammonia total [as N]	30-day average	≤ 869.7 lb/d	Sep	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4733.8 lb/d	Jul	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4163 lb/d	Dec	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4140.2 lb/d	Oct	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4031.2 lb/d	Nov	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4654.6 lb/d	May	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 6071.9 lb/d	Feb	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4134.3 lb/d	Apr	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 5250.1 lb/d	Mar	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4770.7 lb/d	Aug	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 5359.4 lb/d	Jan	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4584 lb/d	Jun	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 4228.4 lb/d	Sep	001
Nitrogen, Kjeldahl, total [as N]	30-day average	report only (mg/L)	all year	001
Nitrogen, Kjeldahl, total [as N]	daily maximum	report only (mg/L)	all year	001
Nitrogen, Kjeldahl, total [as N]	30-day average	report only (lb/d)	all year	001
Nitrogen, Kjeldahl, total [as N]	daily maximum	report only (lb/d)	all year	001
Phosphorus, total [as P]	30-day average	report only (mg/L)	all year	001
Phosphorus, total [as P]	daily maximum	report only (mg/L)	all year	001
Phosphorus, total [as P]	30-day average	report only (lb/d)	all year	001
Phosphorus, total [as P]	daily maximum	report only (lb/d)	all year	001
E. coli	geometric mean	≤ 126 #/100mL	Mar–Nov	001
Toxicity [acute], Ceriodaphnia dubia	daily maximum	≤ 1 N=0;Y=1	all year	001
Toxicity [acute], Pimephales promelas [Fathead Minnow]	daily maximum	≤ 1 N=0;Y=1	all year	001
BOD, carbonaceous [5 day, 20 C]	30-day average	≤ 25 mg/L	all year	001
BOD, carbonaceous [5 day, 20 C]	7-day average	≤ 40 mg/L	all year	001
BOD, carbonaceous [5 day, 20 C]	30-day average	≤ 1835 lb/d	all year	001
BOD, carbonaceous [5 day, 20 C]	7-day average	≤ 2936 lb/d	all year	001
pH	daily minimum	≥ 6 SU	all year	002
pH	daily maximum	≤ 9 SU	all year	002
Solids, total suspended	30-day average	≤ 30 mg/L	all year	002
Solids, total suspended	7-day average	≤ 45 mg/L	all year	002
Solids, total suspended	30-day average	≤ 2202 lb/d	all year	002
Solids, total suspended	7-day average	≤ 3303 lb/d	all year	002
Nitrogen, total [as N]	30-day average	≤ 1303.4 lb/d	all year	002
Nitrogen, total [as N]	daily maximum	≤ 2133.5 lb/d	all year	002
Nitrogen, ammonia total [as N]	30-day average	≤ 16.3 mg/L	May	002
Nitrogen, ammonia total [as N]	30-day average	≤ 20.1 mg/L	Dec	002
Nitrogen, ammonia total [as N]	30-day average	≤ 18.9 mg/L	Mar	002
Nitrogen, ammonia total [as N]	30-day average	≤ 18.6 mg/L	Nov	002
Nitrogen, ammonia total [as N]	30-day average	≤ 8.9 mg/L	Aug	002
Nitrogen, ammonia total [as N]	30-day average	≤ 14.6 mg/L	Oct	002
Nitrogen, ammonia total [as N]	30-day average	≤ 14.3 mg/L	Apr	002
Nitrogen, ammonia total [as N]	30-day average	≤ 12.3 mg/L	Jun	002
Nitrogen, ammonia total [as N]	30-day average	≤ 9.9 mg/L	Sep	002
Nitrogen, ammonia total [as N]	30-day average	≤ 9.4 mg/L	Jul	002
Nitrogen, ammonia total [as N]	30-day average	≤ 20 mg/L	Feb	002
Nitrogen, ammonia total [as N]	30-day average	≤ 20.4 mg/L	Jan	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 19.7 mg/L	May	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 20.1 mg/L	Dec	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 19.7 mg/L	Mar	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 18.6 mg/L	Nov	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 20.9 mg/L	Aug	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 19.8 mg/L	Oct	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 19.8 mg/L	Apr	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 18.9 mg/L	Jun	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 20.8 mg/L	Sep	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 22.6 mg/L	Jul	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 20 mg/L	Feb	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 20.4 mg/L	Jan	002
Nitrogen, ammonia total [as N]	30-day average	≤ 1060.1 lb/d	May	002
Nitrogen, ammonia total [as N]	30-day average	≤ 1440.6 lb/d	Dec	002
Nitrogen, ammonia total [as N]	30-day average	≤ 1233.1 lb/d	Mar	002
Nitrogen, ammonia total [as N]	30-day average	≤ 1332.2 lb/d	Nov	002
Nitrogen, ammonia total [as N]	30-day average	≤ 580.1 lb/d	Aug	002
Nitrogen, ammonia total [as N]	30-day average	≤ 952.4 lb/d	Oct	002
Nitrogen, ammonia total [as N]	30-day average	≤ 927.3 lb/d	Apr	002
Nitrogen, ammonia total [as N]	30-day average	≤ 799.7 lb/d	Jun	002
Nitrogen, ammonia total [as N]	30-day average	≤ 643.4 lb/d	Sep	002
Nitrogen, ammonia total [as N]	30-day average	≤ 611.4 lb/d	Jul	002
Nitrogen, ammonia total [as N]	30-day average	≤ 1416.7 lb/d	Feb	002
Nitrogen, ammonia total [as N]	30-day average	≤ 1448.6 lb/d	Jan	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1407.3 lb/d	May	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1440.6 lb/d	Dec	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1402.9 lb/d	Mar	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1332.2 lb/d	Nov	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1495.6 lb/d	Aug	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1418.6 lb/d	Oct	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1418.2 lb/d	Apr	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1345.1 lb/d	Jun	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1486.8 lb/d	Sep	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1612.9 lb/d	Jul	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1416.7 lb/d	Feb	002
Nitrogen, ammonia total [as N]	daily maximum	≤ 1448.6 lb/d	Jan	002
E. coli	geometric mean	≤ 126 #/100mL	Mar–Nov	002
BOD, carbonaceous [5 day, 20 C]	30-day average	≤ 25 mg/L	all year	002
BOD, carbonaceous [5 day, 20 C]	7-day average	≤ 40 mg/L	all year	002
BOD, carbonaceous [5 day, 20 C]	30-day average	≤ 1835 lb/d	all year	002
BOD, carbonaceous [5 day, 20 C]	7-day average	≤ 2936 lb/d	all year	002

How strict are these limits?

Your permit document is the final word. As JSON: /api/v1/permits/IA0036633 · MCP: https://passage-data.com/mcp