Rock Springs, City of

NPDES permit WY0022357 · 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
23required values missing, on 8 form(s)
8of 31 forms filed late

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

Reporting

Reports are due about 28 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (44)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. centigradeDAILY MX report only all year
001Oxygen, dissolved [DO]DAILY MX report only all year
001BOD, 5-day, 20 deg. CMO AVG <= 30 mg/L all year
001BOD, 5-day, 20 deg. CWKLY AVG <= 45 mg/L all year
001BOD, 5-day, 20 deg. CDAILY MX report only all year
001BOD, 5-day, 20 deg. CMO AVG report only all year
001BOD, 5-day, 20 deg. CWKLY AVG report only all year
001BOD, 5-day, 20 deg. CDAILY MX report only all year
001pHINST MIN >= 6.5 SU all year
001pHINST MAX <= 9 SU all year
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Solids, total suspendedWKLY AVG <= 45 mg/L all year
001Solids, total suspendedDAILY MX report only all year
001Solids, total suspendedMO AVG report only all year
001Solids, total suspendedWKLY AVG report only all year
001Solids, total suspendedDAILY MX report only all year
001Nitrogen, ammonia total [as N]MO AVG <= 3.14 mg/L Jan, Feb, Mar, Apr, Oct, Nov, Dec
001Nitrogen, ammonia total [as N]MO AVG <= 2.74 mg/L May, Jun, Jul, Aug, Sep
001Nitrogen, ammonia total [as N]DAILY MX <= 20.8 mg/L Jan, Feb, Mar, Apr, Oct, Nov, Dec
001Nitrogen, ammonia total [as N]DAILY MX <= 20.5 mg/L May, Jun, Jul, Aug, Sep
001Nitrite + Nitrate total [as N]DAILY MX report only all year
001Hardness, total [as CaCO3]MO AVG report only all year
001Copper, total [as Cu]MO AVG <= 21.3 ug/L all year
001Nickel, total [as Ni]DAILY MX report only all year
001Zinc, total [as Zn]DAILY MX report only all year
001ChlorideMO AVG <= 230 mg/L all year
001ChlorideMO AVG <= 230 mg/L all year
001DurationMO TOTAL report only all year
001Chlorine, total residualDAILY MX <= .011 mg/L all year
001E. coliMO GEOMN <= 630 MPN/100mL Jan, Feb, Mar, Apr, Oct, Nov, Dec
001E. coliMO GEOMN <= 126 MPN/100mL May, Jun, Jul, Aug, Sep
001E. coliDAILY MX <= 630 MPN/100mL Jan, Feb, Mar, Apr, Oct, Nov, Dec
001E. coliDAILY MX <= 235 MPN/100mL May, Jun, Jul, Aug, Sep
001Phosphorus, TotalDAILY MX report only all year
001Solids, total dissolvedDAILY MX report only all year
001Solids, total dissolvedDAILY MX report only all year
001Solids, total dissolved [TDS]DAILY MX report only all year
001FlowMO AVG report only all year
001FlowDAILY MX report only all year
001BOD, 5-day, percent removalMO AV MN >= 85 % all year
001Solids, suspended percent removalMO AV MN >= 85 % all year
001Produced water, oil and greaseDAILY MX report only all year
001Pass/Fail Static Renewal 7 Day Chronic Ceriodaphnia dubia7E <= 0 pass=0;fail=1 all year
001Pass/Fail Static Renewal 7Day Chronic Pimephales promelas7E <= 0 pass=0;fail=1 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