Willmar city of

NPDES permit MN0025259 · Major POTW · effective, expires 2029-03-31 · EPA's file as of 2026-09-19

Check this month's numbers before you file
Watch this permit — $79 a month. Every Monday, from EPA's newest files: the next report due and when, whether EPA's file holds your last one, any change to this permit's limits or status, and the renewal date.

EPA's record, 2025-09-01 to 2026-08-31

0values over a limit
0required values missing, on 0 form(s)
0of 36 forms filed late

Last period with anything received: 2026-08-31.

Reporting

Reports are due about 21 days after each monitoring period ends (the most common figure among MN permits in EPA's filings — check your permit).

Limits in force (57)

OutfallParameterStatisticLimitMonths
D103Specific conductanceMO MAX report only Mar, Sep
D103Oxygen, dissolved [DO]MO MIN >= 6 mg/L Jan, Feb, Mar, Dec
D103Oxygen, dissolved [DO]MO MIN report only Apr, May, Jun, Jul, Aug, Sep, Oct, Nov
D103pHMO MIN >= 6 SU all year
D103pHMO MAX <= 9 SU all year
D103Bicarbonate ion- [as HCO3]MO MAX report only Mar, Sep
D103Solids, total suspendedMO AVG <= 30 mg/L all year
D103Solids, total suspendedMO MAX report only May, Sep
D103Solids, total suspendedMX WK AV <= 45 mg/L all year
D103Solids, total suspendedMO AVG <= 852 kg/d all year
D103Solids, total suspendedMX WK AV <= 1277 kg/d all year
D103Nitrogen, total [as N]MO AVG report only all year
D103Nitrogen, ammonia total [as N]MO AVG report only Apr, May, Jun, Jul, Aug, Sep, Oct, Nov
D103Nitrogen, ammonia total [as N]MO AVG <= 5 mg/L Jan, Feb, Mar, Dec
D103Nitrogen, ammonia total [as N]MO AVG report only Apr, May, Jun, Jul, Aug, Sep, Oct, Nov
D103Nitrogen, ammonia total [as N]MO AVG <= 142 kg/d Jan, Feb, Mar, Dec
D103Nitrogen, Kjeldahl, total [as N]MO AVG report only all year
D103Nitrite + Nitrate total [as N]MO AVG report only all year
D103Phosphorus, total [as P]MO AVG <= 1 mg/L Jan, Feb, Mar, Apr, May, Oct, Nov, Dec
D103Phosphorus, total [as P]MO AVG <= 1 mg/L Jun, Jul, Aug, Sep
D103Phosphorus, total [as P]MO AVG report only Jan, Feb, Mar, Apr, May, Oct, Nov, Dec
D103Phosphorus, total [as P]MO AVG <= 22.1 kg/d Jun, Jul, Aug, Sep
D103Phosphorus, total [as P]ANNL TOT <= 8300 kg/yr all year
D103Calcium, total [as Ca]MO MAX report only Mar, Sep
D103Magnesium, total [as Mg]MO MAX report only Mar, Sep
D103Sodium, total [as Na]MO MAX report only Mar, Sep
D103Potassium, total [as K]MO MAX report only Mar, Sep
D103Chloride [as Cl]DAILY MX <= 612 mg/L all year
D103Sulfate, total [as SO4]MO MAX report only Mar, Sep
D103Hardness, Ca Mg Calculated [mg/L as CaCO3]MO MAX report only Mar, Sep
D103Coliform, fecal MPN + membrane ftl 44.5 CMO GEOMN <= 200 #/100mL May, Jun, Jul, Aug, Sep, Oct
D103Flow, in conduit or thru treatment plantMO AVG report only all year
D103Flow, in conduit or thru treatment plantMO MAX report only all year
D103Flow, in conduit or thru treatment plantMO TOTAL report only all year
D103Solids, total dissolvedMO MAX report only Mar, Sep
D103Mercury, dissolved [as Hg]MO MAX report only May, Sep
D103Mercury, total [as Hg]MO MAX report only May, Sep
D103BOD, carbonaceous [5 day, 20 C]MO AVG <= 15 mg/L all year
D103BOD, carbonaceous [5 day, 20 C]MX WK AV <= 22.5 mg/L all year
D103BOD, carbonaceous [5 day, 20 C]MO AVG <= 426 kg/d all year
D103BOD, carbonaceous [5 day, 20 C]MX WK AV <= 639 kg/d all year
D103BOD, carb-5 day, 20 deg C, percent removalMO AV MN >= 85 % all year
D103Solids, suspended percent removalMO AV MN >= 85 % all year
S107Precipitation, total defined period/inMO TOTAL report only all year
S107pHMO MIN report only all year
S107pHMO MAX report only all year
S107Solids, total suspendedMO AVG report only all year
S107Solids, total suspendedMO MAX report only all year
S107Nitrogen, total [as N]MO AVG report only all year
S107Nitrogen, Kjeldahl, total [as N]MO AVG report only all year
S107Nitrite + Nitrate total [as N]MO AVG report only all year
S107Phosphorus, total [as P]MO AVG report only all year
S107Flow, in conduit or thru treatment plantMO AVG report only all year
S107Flow, in conduit or thru treatment plantMO MAX report only all year
S107Flow, in conduit or thru treatment plantMO TOTAL report only all year
S107BOD, carbonaceous [5 day, 20 C]MO AVG report only all year
S107BOD, carbonaceous [5 day, 20 C]MO MAX report only all year

Built from EPA's ECHO bulk files. EPA's file, not the permit document, is the source: read your permit. Check a report before you file it · All states