CITY OF COLUMBIA FALLS

NPDES permit MT0020036 · Minor POTW · effective, expires 2030-05-31 · 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 14 forms filed late

Last period with anything received: 2026-07-31.

Reporting

Reports are due about 28 days after each monitoring period ends (the most common figure among MT permits in EPA's filings — check your permit).

Limits in force (44)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. centigradeVALUE report only all year
001Flow rateMO AVG report only all year
001Flow rateDAILY MX report only all year
001pHDAILY MN >= 6 SU all year
001pHDAILY MX <= 9 SU all year
001pHVALUE report only all year
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Solids, total suspendedMX WK AV <= 45 mg/L all year
001Solids, total suspendedMO AVG <= 128 lb/d all year
001Solids, total suspendedMX WK AV <= 191 lb/d all year
001Solids, total suspendedMO AVG report only all year
001Oil & GreaseDAILY MX <= 10 mg/L all year
001Oil & GreaseDAILY MX <= 10 mg/L all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, total [as N]MX WK AV report only all year
001Nitrogen, total [as N]MO AVG <= 37.1 lb/d all year
001Nitrogen, total [as N]MX WK AV <= 63.5 lb/d all year
001Nitrogen, total [as N]VALUE report only all year
001Nitrogen, ammonia total [as N]MO AVG report only all year
001Nitrogen, ammonia total [as N]VALUE report only all year
001Nitrogen, Kjeldahl, total [as N]MO AVG report only all year
001Nitrogen, Kjeldahl, total [as N]VALUE report only all year
001Nitrite + Nitrate total [as N]MO AVG report only all year
001Nitrite + Nitrate total [as N]VALUE report only all year
001Phosphorus, total [as P]MO AVG <= 1 mg/L all year
001Phosphorus, total [as P]MO AVG <= 4.6 lb/d all year
001Phosphorus, total [as P]VALUE report only all year
001Hardness, total [as CaCO3]VALUE report only all year
001Zinc, total recoverableVALUE report only all year
001Aluminum, dissolved [as Al]MO AVG report only all year
001Aluminum, dissolved [as Al]DAILY MX report only all year
001Copper, total recoverableVALUE report only all year
001E. coli, MTEC-MFMO GEO <= 630 #/100mL Jan, Feb, Mar, Nov, Dec
001E. coli, MTEC-MFMO GEO <= 126 #/100mL Apr, May, Jun, Jul, Aug, Sep, Oct
001E. coli, MTEC-MFWE <= 1260 #/100mL Jan, Feb, Mar, Nov, Dec
001E. coli, MTEC-MFWE <= 252 #/100mL Apr, May, Jun, Jul, Aug, Sep, Oct
001BOD, carbonaceous [5 day, 20 C]MO AVG <= 25 mg/L all year
001BOD, carbonaceous [5 day, 20 C]MX WK AV <= 40 mg/L all year
001BOD, carbonaceous [5 day, 20 C]MO AVG <= 106 lb/d all year
001BOD, carbonaceous [5 day, 20 C]MX WK AV <= 170 lb/d all year
001BOD, carbonaceous [5 day, 20 C]MO AVG report only all year
001BOD, 5-day, percent removalMINIMUM >= 85 % all year
001Solids, suspended percent removalMINIMUM >= 85 % all year
001Oil and grease visualVALUE 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