CHARLESTOWN W W T P

NPDES permit NH0100765 · Major POTW · administratively continued, expires 2025-09-30 · 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.

This permit expired on 2025-09-30 and is administratively continued: its last limits keep applying until a new permit is issued, and EPA still expects the reports.

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

0values over a limit
20required values missing, on 2 form(s)
3of 14 forms filed late

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

Reporting

Reports are due about 15 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (55)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. centigradeDAILY MX report only Apr, May, Jun
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 <= 50 mg/L all year
001BOD, 5-day, 20 deg. CMO AVG <= 275 lb/d all year
001BOD, 5-day, 20 deg. CDAILY MX <= 459 lb/d all year
001BOD, 5-day, 20 deg. CWKLY AVG <= 413 lb/d all year
001BOD, 5-day, 20 deg. CMO AVG report only all year
001pHMINIMUM >= 6.5 SU all year
001pHMAXIMUM <= 8 SU all year
001pHDAILY MX report only Apr, May, Jun
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Solids, total suspendedWKLY AVG <= 45 mg/L all year
001Solids, total suspendedDAILY MX <= 50 mg/L all year
001Solids, total suspendedMO AVG <= 275 lb/d all year
001Solids, total suspendedDAILY MX <= 459 lb/d all year
001Solids, total suspendedWKLY AVG <= 413 lb/d all year
001Solids, total suspendedMO AVG report only all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, total [as N]DAILY MX report only all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, ammonia total [as N]DAILY MX report only Apr, May, Jun
001Nitrogen, ammonia total [as N]DAILY MX report only Apr, May, Jun
001Nitrogen, Kjeldahl, total [as N]MO AVG report only all year
001Nitrogen, Kjeldahl, total [as N]DAILY MX report only all year
001Nitrite + Nitrate total [as N]MO AVG report only all year
001Nitrite + Nitrate total [as N]DAILY MX report only all year
001Carbon, tot organic [TOC]DAILY MX report only Apr, May, Jun
001Carbon, tot organic [TOC]DAILY MX report only Apr, May, Jun
001Carbon, dissolved organic [as C]DAILY MX report only Apr, May, Jun
001Hardness, total [as CaCO3]DAILY MX report only Apr, May, Jun
001Hardness, total [as CaCO3]DAILY MX report only Apr, May, Jun
001Cadmium, total [as Cd]DAILY MX report only Apr, May, Jun
001Cadmium, total [as Cd]DAILY MX report only Apr, May, Jun
001Copper, total [as Cu]DAILY MX report only Apr, May, Jun
001Copper, total [as Cu]DAILY MX report only Apr, May, Jun
001Lead, total [as Pb]DAILY MX report only Apr, May, Jun
001Lead, total [as Pb]DAILY MX report only Apr, May, Jun
001Nickel, total [as Ni]DAILY MX report only Apr, May, Jun
001Nickel, total [as Ni]DAILY MX report only Apr, May, Jun
001Zinc, total [as Zn]DAILY MX report only Apr, May, Jun
001Zinc, total [as Zn]DAILY MX report only Apr, May, Jun
001Aluminum, total [as Al]DAILY MX report only Apr, May, Jun
001Aluminum, total [as Al]DAILY MX report only Apr, May, Jun
001E. coli, thermotol, MF, MTECMO GEO <= 126 #/100mL all year
001E. coli, thermotol, MF, MTECDAILY MX <= 406 #/100mL all year
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Flow, in conduit or thru treatment plantDAILY MX report only all year
001Flow, in conduit or thru treatment plantROLL AVG <= 1.1 MGD all year
001Chlorine, total residualMO AVG <= 1 mg/L all year
001Chlorine, total residualDAILY MX <= 1 mg/L all year
001BOD, 5-day, percent removalMO AV MN >= 85 % all year
001Solids, suspended percent removalMO AV MN >= 85 % all year
001LC50 Static 48Hr Acute Ceriodaphnia dubiaMO AV MN >= 50 % Apr, May, Jun
001LC50 Static 48Hr Acute Pimephales promelasMO AV MN >= 50 % Apr, May, Jun

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