COMMONWEALTH UTILITIES CORP

NPDES permit MP0020010 · Major POTW · effective, expires 2028-07-31 · EPA's file as of 2026-09-19

Check this month's numbers before you file

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

13values over a limit
0required values missing, on 0 form(s)
0of 68 forms filed late

Last period with anything received: 2026-06-30. Most often over: Enterococci (12), Solids, settleable (1).

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 (380)

OutfallParameterStatisticLimitMonths
001BOD, 5-day, 20 deg. CMO AVG <= 30 mg/L all year
001BOD, 5-day, 20 deg. CMO AVG <= 30 mg/L all year
001BOD, 5-day, 20 deg. CHI WK AV <= 45 mg/L all year
001BOD, 5-day, 20 deg. CHI WK AV <= 45 mg/L all year
001BOD, 5-day, 20 deg. CMO AVG <= 1202 lb/d all year
001BOD, 5-day, 20 deg. CMO AVG <= 1202 lb/d all year
001BOD, 5-day, 20 deg. CHI WK AV <= 1803 lb/d all year
001BOD, 5-day, 20 deg. CHI WK AV <= 1803 lb/d all year
001pHMINIMUM >= 6 SU all year
001pHMINIMUM >= 6 SU all year
001pHMAXIMUM <= 9 SU all year
001pHMAXIMUM <= 9 SU all year
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Solids, total suspendedHI WK AV <= 45 mg/L all year
001Solids, total suspendedHI WK AV <= 45 mg/L all year
001Solids, total suspendedMO AVG <= 1202 lb/d all year
001Solids, total suspendedMO AVG <= 1202 lb/d all year
001Solids, total suspendedHI WK AV <= 1803 lb/d all year
001Solids, total suspendedHI WK AV <= 1803 lb/d all year
001Solids, settleableMO AVG <= 1 mL/L all year
001Solids, settleableMO AVG <= 1 mL/L all year
001Solids, settleableDAILY MX <= 2 mL/L all year
001Solids, settleableDAILY MX <= 2 mL/L all year
001Nitrogen, total [as N]MO AVG <= 33 mg/L all year
001Nitrogen, total [as N]MO AVG <= 33 mg/L all year
001Nitrogen, total [as N]DAILY MX <= 67 mg/L all year
001Nitrogen, total [as N]DAILY MX <= 67 mg/L all year
001Phosphorus, total [as P]MO AVG <= 2.2 mg/L all year
001Phosphorus, total [as P]MO AVG <= 2.2 mg/L all year
001Phosphorus, total [as P]DAILY MX <= 4.4 mg/L all year
001Phosphorus, total [as P]DAILY MX <= 4.4 mg/L all year
001Cyanide, total [as CN]DAILY MX report only all year
001Cyanide, total [as CN]DAILY MX report only all year
001Arsenic, total recoverableDAILY MX report only all year
001Arsenic, total recoverableDAILY MX report only all year
001Selenium, total recoverableDAILY MX report only all year
001Selenium, total recoverableDAILY MX report only all year
001Thallium, total recoverableDAILY MX report only all year
001Thallium, total recoverableDAILY MX report only all year
001Beryllium, total recoverable [as Be]DAILY MX report only all year
001Beryllium, total recoverable [as Be]DAILY MX report only all year
001Chromium, hexavalent [as Cr]DAILY MX report only all year
001Chromium, hexavalent [as Cr]DAILY MX report only all year
001Chromium, trivalent [as Cr]DAILY MX report only all year
001Chromium, trivalent [as Cr]DAILY MX report only all year
001Nickel, total recoverableDAILY MX report only all year
001Nickel, total recoverableDAILY MX report only all year
001Silver total recoverableDAILY MX report only all year
001Silver total recoverableDAILY MX report only all year
001Zinc, total recoverableDAILY MX report only all year
001Zinc, total recoverableDAILY MX report only all year
001Cadmium, total recoverableDAILY MX report only all year
001Cadmium, total recoverableDAILY MX report only all year
001Lead, total recoverableDAILY MX report only all year
001Lead, total recoverableDAILY MX report only all year
001Copper, total recoverableDAILY MX report only all year
001Copper, total recoverableDAILY MX report only all year
001Antimony, total recoverableDAILY MX report only all year
001Antimony, total recoverableDAILY MX report only all year
0012-Methyl-4,6-dinitrophenolDAILY MX report only all year
0012-Methyl-4,6-dinitrophenolDAILY MX report only all year
001Phosphate, ortho [as P]MO AVG <= 2.2 mg/L all year
001Phosphate, ortho [as P]MO AVG <= 2.2 mg/L all year
001Phosphate, ortho [as P]DAILY MX <= 4.4 mg/L all year
001Phosphate, ortho [as P]DAILY MX <= 4.4 mg/L all year
001DichlorobromomethaneDAILY MX report only all year
001DichlorobromomethaneDAILY MX report only all year
001Carbon tetrachlorideDAILY MX report only all year
001Carbon tetrachlorideDAILY MX report only all year
0011,2-DichloroethaneDAILY MX report only all year
0011,2-DichloroethaneDAILY MX report only all year
001BromoformDAILY MX report only all year
001BromoformDAILY MX report only all year
001DibromochloromethaneDAILY MX report only all year
001DibromochloromethaneDAILY MX report only all year
001ChloroformDAILY MX report only all year
001ChloroformDAILY MX report only all year
001TolueneDAILY MX report only all year
001TolueneDAILY MX report only all year
001BenzeneDAILY MX report only all year
001BenzeneDAILY MX report only all year
001.delta.-BHCDAILY MX report only all year
001.delta.-BHCDAILY MX report only all year
001AcenaphthyleneDAILY MX report only all year
001AcenaphthyleneDAILY MX report only all year
001AcenaphtheneDAILY MX report only all year
001AcenaphtheneDAILY MX report only all year
001AcroleinDAILY MX report only all year
001AcroleinDAILY MX report only all year
001AcrylonitrileDAILY MX report only all year
001AcrylonitrileDAILY MX report only all year
001AnthraceneDAILY MX report only all year
001AnthraceneDAILY MX report only all year
001Benzo[b]fluorantheneDAILY MX report only all year
001Benzo[b]fluorantheneDAILY MX report only all year
001Benzo[k]fluorantheneDAILY MX report only all year
001Benzo[k]fluorantheneDAILY MX report only all year
001Benzo[a]pyreneDAILY MX report only all year
001Benzo[a]pyreneDAILY MX report only all year
001Bis[2-chloroethyl] etherDAILY MX report only all year
001Bis[2-chloroethyl] etherDAILY MX report only all year
001Bis[2-chloroethoxy]methaneDAILY MX report only all year
001Bis[2-chloroethoxy]methaneDAILY MX report only all year
001Bis[2-chloroisopropyl] etherDAILY MX report only all year
001Bis[2-chloroisopropyl] etherDAILY MX report only all year
001Butyl benzyl phthalateDAILY MX report only all year
001Butyl benzyl phthalateDAILY MX report only all year
001ChlorobenzeneDAILY MX report only all year
001ChlorobenzeneDAILY MX report only all year
001ChryseneDAILY MX report only all year
001ChryseneDAILY MX report only all year
001Diethyl phthalateDAILY MX report only all year
001Diethyl phthalateDAILY MX report only all year
001Dimethyl phthalateDAILY MX report only all year
001Dimethyl phthalateDAILY MX report only all year
0011,2-DiphenylhydrazineDAILY MX report only all year
0011,2-DiphenylhydrazineDAILY MX report only all year
001Endosulfan sulfateDAILY MX report only all year
001Endosulfan sulfateDAILY MX report only all year
001.beta.-EndosulfanDAILY MX report only all year
001.beta.-EndosulfanDAILY MX report only all year
001.alpha.-EndosulfanDAILY MX report only all year
001.alpha.-EndosulfanDAILY MX report only all year
001Endrin aldehydeDAILY MX report only all year
001Endrin aldehydeDAILY MX report only all year
001EthylbenzeneDAILY MX report only all year
001EthylbenzeneDAILY MX report only all year
001FluorantheneDAILY MX report only all year
001FluorantheneDAILY MX report only all year
001FluoreneDAILY MX report only all year
001FluoreneDAILY MX report only all year
001HexachlorocyclopentadieneDAILY MX report only all year
001HexachlorocyclopentadieneDAILY MX report only all year
001HexachlorobutadieneDAILY MX report only all year
001HexachlorobutadieneDAILY MX report only all year
001HexachloroethaneDAILY MX report only all year
001HexachloroethaneDAILY MX report only all year
001Indeno[1,2,3-cd]pyreneDAILY MX report only all year
001Indeno[1,2,3-cd]pyreneDAILY MX report only all year
001IsophoroneDAILY MX report only all year
001IsophoroneDAILY MX report only all year
001Methyl bromide [Bromomethane]DAILY MX report only all year
001Methyl bromide [Bromomethane]DAILY MX report only all year
001Methyl chloride [Chloromethane]DAILY MX report only all year
001Methyl chloride [Chloromethane]DAILY MX report only all year
001Methylene chlorideDAILY MX report only all year
001Methylene chlorideDAILY MX report only all year
001N-Nitrosodi-N-propylamineDAILY MX report only all year
001N-Nitrosodi-N-propylamineDAILY MX report only all year
001N-NitrosodiphenylamineDAILY MX report only all year
001N-NitrosodiphenylamineDAILY MX report only all year
001N-Nitrosodimethylamine [NDMA]DAILY MX report only all year
001N-Nitrosodimethylamine [NDMA]DAILY MX report only all year
001NitrobenzeneDAILY MX report only all year
001NitrobenzeneDAILY MX report only all year
001PhenanthreneDAILY MX report only all year
001PhenanthreneDAILY MX report only all year
001PyreneDAILY MX report only all year
001PyreneDAILY MX report only all year
001TetrachloroethyleneDAILY MX report only all year
001TetrachloroethyleneDAILY MX report only all year
0011,1-DichloroethaneDAILY MX report only all year
0011,1-DichloroethaneDAILY MX report only all year
0011,1-DichloroethyleneDAILY MX report only all year
0011,1-DichloroethyleneDAILY MX report only all year
0011,1,1-TrichloroethaneDAILY MX report only all year
0011,1,1-TrichloroethaneDAILY MX report only all year
0011,1,2-TrichloroethaneDAILY MX report only all year
0011,1,2-TrichloroethaneDAILY MX report only all year
0011,1,2,2-TetrachloroethaneDAILY MX report only all year
0011,1,2,2-TetrachloroethaneDAILY MX report only all year
001Benzo[ghi]peryleneDAILY MX report only all year
001Benzo[ghi]peryleneDAILY MX report only all year
001Benzo[a]anthraceneDAILY MX report only all year
001Benzo[a]anthraceneDAILY MX report only all year
0011,2-DichlorobenzeneDAILY MX report only all year
0011,2-DichlorobenzeneDAILY MX report only all year
0011,2-DichloropropaneDAILY MX report only all year
0011,2-DichloropropaneDAILY MX report only all year
001trans-1,2-DichloroethyleneDAILY MX report only all year
001trans-1,2-DichloroethyleneDAILY MX report only all year
0011,2,4-TrichlorobenzeneDAILY MX report only all year
0011,2,4-TrichlorobenzeneDAILY MX report only all year
001Dibenz[a,h]anthraceneDAILY MX report only all year
001Dibenz[a,h]anthraceneDAILY MX report only all year
0011,3-DichlorobenzeneDAILY MX report only all year
0011,3-DichlorobenzeneDAILY MX report only all year
0011,4-DichlorobenzeneDAILY MX report only all year
0011,4-DichlorobenzeneDAILY MX report only all year
0012-Chloroethyl vinyl ether, [mixed]DAILY MX report only all year
0012-Chloroethyl vinyl ether, [mixed]DAILY MX report only all year
0012-ChloronaphthaleneDAILY MX report only all year
0012-ChloronaphthaleneDAILY MX report only all year
0012-ChlorophenolDAILY MX report only all year
0012-ChlorophenolDAILY MX report only all year
0012-NitrophenolDAILY MX report only all year
0012-NitrophenolDAILY MX report only all year
001Di-n-octyl phthalateDAILY MX report only all year
001Di-n-octyl phthalateDAILY MX report only all year
0012,4-DichlorophenolDAILY MX report only all year
0012,4-DichlorophenolDAILY MX report only all year
0012,4-DimethylphenolDAILY MX report only all year
0012,4-DimethylphenolDAILY MX report only all year
0012,4-DinitrotolueneDAILY MX report only all year
0012,4-DinitrotolueneDAILY MX report only all year
0012,4-DinitrophenolDAILY MX report only all year
0012,4-DinitrophenolDAILY MX report only all year
0012,4,6-TrichlorophenolDAILY MX report only all year
0012,4,6-TrichlorophenolDAILY MX report only all year
0012,6-DinitrotolueneDAILY MX report only all year
0012,6-DinitrotolueneDAILY MX report only all year
0013,3'-DichlorobenzidineDAILY MX report only all year
0013,3'-DichlorobenzidineDAILY MX report only all year
0014-Bromophenyl phenyl etherDAILY MX report only all year
0014-Bromophenyl phenyl etherDAILY MX report only all year
0014-Chlorophenyl phenyl etherDAILY MX report only all year
0014-Chlorophenyl phenyl etherDAILY MX report only all year
0014-NitrophenolDAILY MX report only all year
0014-NitrophenolDAILY MX report only all year
001PCB-1016DAILY MX report only all year
001PCB-1016DAILY MX report only all year
0012,3,7,8-Tetrachlorodibenzo-p-dioxinDAILY MX report only all year
0012,3,7,8-Tetrachlorodibenzo-p-dioxinDAILY MX report only all year
001PhenolDAILY MX report only all year
001PhenolDAILY MX report only all year
001NaphthaleneDAILY MX report only all year
001NaphthaleneDAILY MX report only all year
001PentachlorophenolDAILY MX report only all year
001PentachlorophenolDAILY MX report only all year
001Di[2-ethylhexyl] phthalate [DEHP]DAILY MX report only all year
001Di[2-ethylhexyl] phthalate [DEHP]DAILY MX report only all year
001Di-n-butyl phthalateDAILY MX report only all year
001Di-n-butyl phthalateDAILY MX report only all year
001BenzidineDAILY MX report only all year
001BenzidineDAILY MX report only all year
001Vinyl chlorideDAILY MX report only all year
001Vinyl chlorideDAILY MX report only all year
001TrichloroethyleneDAILY MX report only all year
001TrichloroethyleneDAILY MX report only all year
0014,4'-DDTDAILY MX report only all year
0014,4'-DDTDAILY MX report only all year
0014,4'-DDDDAILY MX report only all year
0014,4'-DDDDAILY MX report only all year
0014,4'-DDEDAILY MX report only all year
0014,4'-DDEDAILY MX report only all year
001AldrinDAILY MX report only all year
001AldrinDAILY MX report only all year
001.alpha.-BHCDAILY MX report only all year
001.alpha.-BHCDAILY MX report only all year
001.beta.-BHCDAILY MX report only all year
001.beta.-BHCDAILY MX report only all year
001.gamma.-BHCDAILY MX report only all year
001.gamma.-BHCDAILY MX report only all year
001Chlordane [tech mix. and metabolites]DAILY MX report only all year
001Chlordane [tech mix. and metabolites]DAILY MX report only all year
001DieldrinDAILY MX report only all year
001DieldrinDAILY MX report only all year
001EndrinDAILY MX report only all year
001EndrinDAILY MX report only all year
001ToxapheneDAILY MX report only all year
001ToxapheneDAILY MX report only all year
001HeptachlorDAILY MX report only all year
001HeptachlorDAILY MX report only all year
001Heptachlor epoxideDAILY MX report only all year
001Heptachlor epoxideDAILY MX report only all year
001PCB-1221DAILY MX report only all year
001PCB-1221DAILY MX report only all year
001PCB-1232DAILY MX report only all year
001PCB-1232DAILY MX report only all year
001PCB-1242DAILY MX report only all year
001PCB-1242DAILY MX report only all year
001PCB-1248DAILY MX report only all year
001PCB-1248DAILY MX report only all year
001PCB-1254DAILY MX report only all year
001PCB-1254DAILY MX report only all year
001PCB-1260DAILY MX report only all year
001PCB-1260DAILY MX report only all year
001HexachlorobenzeneDAILY MX report only all year
001HexachlorobenzeneDAILY MX report only all year
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Flow, in conduit or thru treatment plantWKLY AVG report only all year
001Flow, in conduit or thru treatment plantWKLY AVG report only all year
001Flow, in conduit or thru treatment plantDAILY MX report only all year
001Flow, in conduit or thru treatment plantDAILY MX report only all year
001Enterococci30DA GM <= 3080 MPN/100mL all year
001Enterococci30DA GM <= 3080 MPN/100mL all year
001Enterococci30DA GM <= 3080 MPN/100mL all year
001Enterococci30DA GM <= 3080 MPN/100mL all year
001EnterococciDAILY MX <= 24288 MPN/100mL all year
001EnterococciDAILY MX <= 24288 MPN/100mL all year
001EnterococciDAILY MX <= 11440 MPN/100mL all year
001EnterococciDAILY MX <= 11440 MPN/100mL all year
0014-Chloro-3-methylphenolDAILY MX report only all year
0014-Chloro-3-methylphenolDAILY MX report only all year
001Oil & grease, total recoverable [Q/C]DAILY MX <= 15 mg/L all year
001Oil & grease, total recoverable [Q/C]DAILY MX <= 15 mg/L all year
001Mercury, total recoverableDAILY MX report only all year
001Mercury, total recoverableDAILY MX report only all year
0011,3-DichloropropeneDAILY MX report only all year
0011,3-DichloropropeneDAILY MX report only all year
001BOD, 5-day, percent removalMO AV MN >= 85 % all year
001BOD, 5-day, percent removalMO AV MN >= 85 % all year
001Solids, suspended percent removalMO AV MN >= 85 % all year
001Solids, suspended percent removalMO AV MN >= 85 % all year
001ChloroethaneDAILY MX report only all year
001ChloroethaneDAILY MX report only all year
001Pass/Fail Static 20 Minute Fertilization Chronic Strongylocentrotus purpuratusMO AVG report only all year
001Pass/Fail Static 20 Minute Fertilization Chronic Strongylocentrotus purpuratusMO AVG report only all year
001Pass/Fail Static 20 Minute Fertilization Chronic Strongylocentrotus purpuratusDAILY MX report only all year
001Pass/Fail Static 20 Minute Fertilization Chronic Strongylocentrotus purpuratusDAILY MX report only all year
001Pass/Fail Static 20 Minute Fertilization Chronic Dendraster excentricusMO AVG report only all year
001Pass/Fail Static 20 Minute Fertilization Chronic Dendraster excentricusMO AVG report only all year
001Pass/Fail Static 20 Minute Fertilization Chronic Dendraster excentricusDAILY MX report only all year
001Pass/Fail Static 20 Minute Fertilization Chronic Dendraster excentricusDAILY MX report only all year
INFBOD, 5-day, 20 deg. CMO AVG report only all year
INFBOD, 5-day, 20 deg. CMO AVG report only all year
INFBOD, 5-day, 20 deg. CHI WK AV report only all year
INFBOD, 5-day, 20 deg. CHI WK AV report only all year
INFBOD, 5-day, 20 deg. CMO AVG report only all year
INFBOD, 5-day, 20 deg. CMO AVG report only all year
INFBOD, 5-day, 20 deg. CHI WK AV report only all year
INFBOD, 5-day, 20 deg. CHI WK AV report only all year
INFSolids, total suspendedMO AVG report only all year
INFSolids, total suspendedMO AVG report only all year
INFSolids, total suspendedHI WK AV report only all year
INFSolids, total suspendedHI WK AV report only all year
INFSolids, total suspendedMO AVG report only all year
INFSolids, total suspendedMO AVG report only all year
INFSolids, total suspendedHI WK AV report only all year
INFSolids, total suspendedHI WK AV report only all year
RW01Temperature, water deg. centigradeMO AVG report only all year
RW01Temperature, water deg. centigradeMO AVG report only all year
RW01TurbidityMO AVG report only all year
RW01TurbidityMO AVG report only all year
RW01Oxygen, dissolved [DO]MO AVG report only all year
RW01Oxygen, dissolved [DO]MO AVG report only all year
RW01pHMO AVG report only all year
RW01pHMO AVG report only all year
RW01Phosphorus, total [as P]MO AVG report only all year
RW01Phosphorus, total [as P]MO AVG report only all year
RW01Phosphate, ortho [as P]MO AVG report only all year
RW01Phosphate, ortho [as P]MO AVG report only all year
RW01Nitrogen, TotalMO AVG report only all year
RW01Nitrogen, TotalMO AVG report only all year
RW01EnterococciMO AVG report only all year
RW01EnterococciMO AVG report only all year
RW02Temperature, water deg. centigradeMO AVG report only all year
RW02Temperature, water deg. centigradeMO AVG report only all year
RW02TurbidityMO AVG report only all year
RW02TurbidityMO AVG report only all year
RW02Oxygen, dissolved [DO]MO AVG report only all year
RW02Oxygen, dissolved [DO]MO AVG report only all year
RW02pHMO AVG report only all year
RW02pHMO AVG report only all year
RW02Phosphorus, total [as P]MO AVG report only all year
RW02Phosphorus, total [as P]MO AVG report only all year
RW02Phosphate, ortho [as P]MO AVG report only all year
RW02Phosphate, ortho [as P]MO AVG report only all year
RW02Nitrogen, TotalMO AVG report only all year
RW02Nitrogen, TotalMO AVG report only all year
RW02EnterococciMO AVG report only all year
RW02EnterococciMO AVG report only all year
RWC0Temperature, water deg. centigradeMO AVG report only all year
RWC0Temperature, water deg. centigradeMO AVG report only all year
RWC0TurbidityMO AVG report only all year
RWC0TurbidityMO AVG report only all year
RWC0Oxygen, dissolved [DO]MO AVG report only all year
RWC0Oxygen, dissolved [DO]MO AVG report only all year
RWC0pHMO AVG report only all year
RWC0pHMO AVG report only all year
RWC0Phosphorus, total [as P]MO AVG report only all year
RWC0Phosphorus, total [as P]MO AVG report only all year
RWC0Phosphate, ortho [as P]MO AVG report only all year
RWC0Phosphate, ortho [as P]MO AVG report only all year
RWC0Nitrogen, TotalMO AVG report only all year
RWC0Nitrogen, TotalMO AVG report only all year
RWC0EnterococciMO AVG report only all year
RWC0EnterococciMO AVG 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