DirtyWaterWatch

New Hampshire / Dischargers /

Town of Exeter DPW (Exeter WWTP, 13 Newfields Rd, and CSO 003)

CSO · New Hampshire · Exeter, Stratham, Hampton

NPDES permit
NH0100871
Outfalls
1 with coordinates in the registry
Receiving waters
Clemson Pond (CSO 003; tide gate to Squamscott River); Squamscott River (Outfall 001); Squamscott River
Tracked waters
Squamscott River, NH, Exeter River, NH
Events tracked
45 discharges · latest Sep 17, 2026, 11:46 PM EDT
Volume reported
5,680,921 gallons across the 40 discharges that give a volume (5 without one)

Source: discharger record from the project's research and EPA ECHO (dischargers.json); counts from the 45 event records below, as of 2026-11-02 11:56 UTC.

How it tells the public

HTML table 'Notice of Combined Sewer Overflow (CSO) at Outfall #003 Located at Clemson Pond' (Date / Total Gallons / Description) on https://www.exeternh.gov/publicworks/combined-sewer-sanitary-sewer-overflows. The town has general E-News and Mailchimp newsletters; no CSO-specific list. | Dated prose list on the same page https://www.exeternh.gov/publicworks/combined-sewer-sanitary-sewer-overflows, plus an SSO table (Date / Total Gallons / Description).

Source: the project's research on each operator's notification channel (research/<state>/dischargers.json), checked by fetching the operator's pages.

Outfalls

Source: water outlines from OpenBoatLaunch and OpenStreetMap contributors (ODbL); outfalls from EPA ECHO and the state outfall layers; modeled reaches computed by DirtyWaterWatch from USGS NLDI, NHDPlus and the nearest USGS gauge (Jobson 1996); basemap OpenFreeMap and OpenMapTiles.

1 outfall in the registry
  • 003 Tidal Gate of Clemson Pond · CSO · Squamscott River

Source: EPA ECHO CSO outfall inventory matched to waters (data/outfalls-ne.json).

Event history

Events reported for Town of Exeter DPW (Exeter WWTP, 13 Newfields Rd, and CSO 003), newest first
StartEnd Water OutfallTypeVolumeSourceLinks
Sep 17, 2026, 11:46 PM EDT Sep 17, 2026, 11:48 PM EDT Squamscott River, NH Wastewater Treatment Plant Treatment plant bypass 488 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2026-09-17:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice Event: Treatment plant bypass, Town of Exeter WWTP, Sep 17, 2026, 11:46 PM EDT · Map
Jun 25, 2026, 1:38 AM EDT Jun 25, 2026, 1:43 AM EDT Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 340 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2026-06-25:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice Event: Treatment plant bypass, Town of Exeter WWTP, Jun 25, 2026, 1:38 AM EDT · Map
Oct 31, 2025, 2:38 AM EDT Oct 31, 2025, 2:41 AM EDT Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 2,292 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2025-10-31:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Oct 8, 2025, 11:27 AM EDT Oct 8, 2025, 11:30 AM EDT Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 3,750 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2025-10-08:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Oct 5, 2025, 7:17 AM EDT Oct 5, 2025, 7:20 AM EDT Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 2,709 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2025-10-05:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Sep 30, 2025, 12:00 PM EDT Oct 3, 2025, 10:30 AM EDT “Little River” (not placed) not stated Sanitary sewer overflowrevised 8,460 gal EPA ECHO Sewer Overflow and Bypass Event report (reported to regulators) via ECHO NPDES Sewer Overflow and Bypass Event Dataset (eRule Phase 2, current versions), record NH0100871:4:1, reported Oct 2, 2025, 8:00 PM EDT, retrieved 2026-11-02 11:54 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Sep 30, 2025 ended, time not reported “Little River” (not placed) Elm Street to Gilman Street. Inadvertant private sewer connection to storm drain was discovered. Use was discontinued im Sanitary sewer overflow “unknown” Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2025-09-30:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Mar 7, 2025, 11:38 AM EST ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 40,278 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2025-03-07:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Dec 12, 2023, 10:50 PM EST Dec 12, 2023, 11:05 PM EST Squamscott River, NH 003 Tidal Gate of Clemson Pond Combined sewer overflowrevised 14 gal EPA ECHO Sewer Overflow and Bypass Event report (reported to regulators) via ECHO NPDES Sewer Overflow and Bypass Event Dataset (eRule Phase 2, current versions), record NH0100871:2:1, reported Dec 13, 2023, 7:00 PM EST, retrieved 2026-11-02 11:54 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Dec 12, 2023, 10:50 PM EST Dec 12, 2023, 11:05 PM EST Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Spring St, Water St) Combined sewer overflow 14,072 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2023-12-12:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Dec 12, 2023, 10:16 PM EST ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 9,646 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2023-12-12:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
May 30, 2023 ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 4,720 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2023-05-30:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Apr 20, 2023 ended, time not reported not placed 110 Front Street - Blockage in a sewer manhole Sanitary sewer overflow 100 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2023-04-20:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Mar 18, 2023 ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 2,000 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2023-03-18:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Jan 23, 2023 ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 2,000 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2023-01-23:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Dec 23, 2022 ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 18,611 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2022-12-23:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Jul 21, 2022 ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 5,000 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2022-07-21:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Jul 17, 2022 ended, time not reported not placed Exeter Hospital, 5 Alumni Dr Sanitary sewer overflow “100-150” Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2022-07-17:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
May 28, 2021 ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 10,000 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2021-05-28:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Dec 17, 2020 ended, time not reported not placed 115 Court St Sanitary sewer overflow 65 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2020-12-17:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Apr 20, 2020 Apr 21, 2020 Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 800,000 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2020-04-20:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Feb 28, 2020 ended, time not reported not placed Hilton Ave SSO Sanitary sewer overflow not reported Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2020-02-28:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Nov 26, 2019 ended, time not reported not placed 45 Hilton Ave SSO Sanitary sewer overflow not reported Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2019-11-26:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Nov 23, 2019 ended, time not reported not placed Between 45-47 Hilton Ave SSO Sanitary sewer overflow not reported Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2019-11-23:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Sep 19, 2019 ended, time not reported Squamscott River, NH 001 WWTP outfall 001 Treatment plant bypass 18,750 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2019-09-19:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Jul 9, 2019 ended, time not reported not placed 11 Newfields Rd, air release valve on the force main was hit during the installation causing a SSO Sanitary sewer overflow 180 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2019-07-09:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
May 22, 2019 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate Combined sewer overflow 164,850 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2019-05-22:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Apr 25, 2019 ended, time not reported Squamscott River, NH not stated Treatment plant bypass 40,270 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:bypass:2019-04-25:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Mar 10, 2019 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate Combined sewer overflow 420,170 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2019-03-10:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Mar 9, 2019 Mar 10, 2019 not placed A sewer force main break caused SSO Sanitary sewer overflow 700,000 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2019-03-09:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Feb 21, 2019 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate Combined sewer overflow 20,120 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2019-02-21:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Feb 21, 2019 ended, time not reported not placed A sewer force main break caused two SSO's Sanitary sewer overflow 26,750 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2019-02-21:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Jan 24, 2019 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Spring St) Combined sewer overflow 31,442 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2019-01-24:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Nov 28, 2018 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Spring St) Combined sewer overflow 25,660 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2018-11-28:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Nov 27, 2018 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Spring St, Water St) Combined sewer overflow 1.64 million gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2018-11-27:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Nov 27, 2018 ended, time not reported not placed SSO Sanitary sewer overflow 2,200 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2018-11-27:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Nov 3, 2018 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Spring St, Water St) Combined sewer overflow 10,920 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2018-11-03:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Sep 18, 2018 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Spring St, Water St) Combined sewer overflow 518,790 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2018-09-18:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Aug 3, 2018 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Spring St) Combined sewer overflow 12,760 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2018-08-03:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Jun 20, 2018 ended, time not reported not placed 30 Charter St Sanitary sewer overflow 5 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2018-06-20:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Apr 16, 2018 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Spring St) Combined sewer overflow 260,790 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2018-04-16:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Apr 16, 2018 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate (CSO structures: Water St) Combined sewer overflow 132,990 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2018-04-16:2, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Apr 9, 2017 ended, time not reported Exeter River, NH SSO reported into Exeter River Sanitary sewer overflow 320,100 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2017-04-09:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Apr 6, 2017 Apr 7, 2017 Squamscott River, NH 003 Clemson Pond tide gate Combined sewer overflow 398,160 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2017-04-06:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Oct 21, 2016 ended, time not reported Squamscott River, NH 003 Clemson Pond tide gate Combined sewer overflow 18,191 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:cso:2016-10-21:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below · Map
Full record (older than 180 days, so no page of its own)

This record in the archive list
Mar 9, 2016 ended, time not reported not placed SSO Sanitary sewer overflow 102 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2016-03-09:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list
Jan 10, 2016 ended, time not reported not placed Wet weather SSO due to 1.87" of precipitation Sanitary sewer overflow 6,200 gal Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via nh-permittees, record exeter:sso:2016-01-10:1, the source gives no report time, retrieved 2026-11-02 11:55 UTC · notice record below
Full record (older than 180 days, so no page of its own)

This record in the archive list

History

  • Discharge events, last 12 months0Dec 2025 to Nov 2026; partly covered or sparse source
  • Days with a discharge, last 12 months0Dec 2025 to Nov 2026; partly covered or sparse source
  • Hours under advisory, last 12 months0Dec 2025 to Nov 2026; on this discharger's reports; partly covered or sparse source
  • 2025 season under advisory0.0%May to October, partly covered; 0 h

Discharge events per month

4 events, Jan 2022 to Nov 2026.

  • Combined sewer overflow
  • Sanitary sewer overflow
  • Bypass, blended or other
  • No source
  • Partly covered or sparse source
No sourceNo source

No source covers 2025-10 to 2026-11. NH permittees publish on their own pages; each discharger's record begins on a different date.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2022-01-01 to 2025-09-30.

Show table
Discharge events per month
MonthCombined sewer overflowSanitary sewer overflowBypass, blended or otherTotalCounted fromCoverage
Jan 20220000
Feb 20220000
Mar 20220000
Apr 20220000
May 20220000
Jun 20220000
Jul 20220101Source records
Aug 20220000
Sep 20220000
Oct 20220000
Nov 20220000
Dec 20220000
Jan 20230000
Feb 20230000
Mar 20230000
Apr 20230101Source records
May 20230000
Jun 20230000
Jul 20230000
Aug 20230000
Sep 20230000
Oct 20230000
Nov 20230000
Dec 20231001Source records
Jan 20240000
Feb 20240000
Mar 20240000
Apr 20240000
May 20240000
Jun 20240000
Jul 20240000
Aug 20240000
Sep 20240000
Oct 20240000
Nov 20240000
Dec 20240000
Jan 20250000
Feb 20250000
Mar 20250000
Apr 20250000
May 20250000
Jun 20250000
Jul 20250000
Aug 20250000
Sep 20250101Source recordsPartly covered or sparse source
Oct 20250000No source
Nov 20250000No source
Dec 20250000No source
Jan 20260000No source
Feb 20260000No source
Mar 20260000No source
Apr 20260000No source
May 20260000No source
Jun 20260000No source
Jul 20260000No source
Aug 20260000No source
Sep 20260000No source
Oct 20260000No source
Nov 20260000No source

Hours under advisory per month

Hours this discharger's reports put a water under an advisory, by the map's red rules.

  • Advisory in effect
  • No source
  • Partly covered or sparse source
No sourceNo source

No source covers 2025-10 to 2026-11. 26 discharge events have no reported end and no ongoing status; under the status rules they set caution, not an advisory, and add no hours here. Official beach and cyanobacteria advisories are counted on water pages only. NH permittees publish on their own pages; each discharger's record begins on a different date.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2016-01-10 to 2025-09-30.

Show table
Hours under advisory per month
MonthHours under advisoryFrom discharge windowsHours in monthCoverage
Jan 202200744
Feb 202200672
Mar 202200744
Apr 202200720
May 202200744
Jun 202200720
Jul 202200744
Aug 202200744
Sep 202200720
Oct 202200744
Nov 202200720
Dec 202200744
Jan 202300744
Feb 202300672
Mar 202300744
Apr 202300720
May 202300744
Jun 202300720
Jul 202300744
Aug 202300744
Sep 202300720
Oct 202300744
Nov 202300720
Dec 20237272744
Jan 202400744
Feb 202400696
Mar 202400744
Apr 202400720
May 202400744
Jun 202400720
Jul 202400744
Aug 202400744
Sep 202400720
Oct 202400744
Nov 202400720
Dec 202400744
Jan 202500744
Feb 202500672
Mar 202500744
Apr 202500720
May 202500744
Jun 202500720
Jul 202500744
Aug 202500744
Sep 202500720Partly covered or sparse source
Oct 202500744No source
Nov 202500720No source
Dec 202500744No source
Jan 202600744No source
Feb 202600672No source
Mar 202600744No source
Apr 202600720No source
May 202600744No source
Jun 202600720No source
Jul 202600744No source
Aug 202600744No source
Sep 202600720No source
Oct 202600744No source
Nov 20260032No source

Days with a discharge per month

A day counts when any counted discharge was under way on it (start to reported end, local time); an event with no end counts its start day.

  • No source
  • Partly covered or sparse source
No sourceNo source

No source covers 2025-10 to 2026-11.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2022-01-01 to 2025-09-30.

Show table
Days with a discharge per month
MonthDays with a dischargeCoverage
Jan 20220
Feb 20220
Mar 20220
Apr 20220
May 20220
Jun 20220
Jul 20221
Aug 20220
Sep 20220
Oct 20220
Nov 20220
Dec 20220
Jan 20230
Feb 20230
Mar 20230
Apr 20231
May 20230
Jun 20230
Jul 20230
Aug 20230
Sep 20230
Oct 20230
Nov 20230
Dec 20231
Jan 20240
Feb 20240
Mar 20240
Apr 20240
May 20240
Jun 20240
Jul 20240
Aug 20240
Sep 20240
Oct 20240
Nov 20240
Dec 20240
Jan 20250
Feb 20250
Mar 20250
Apr 20250
May 20250
Jun 20250
Jul 20250
Aug 20250
Sep 20251Partly covered or sparse source
Oct 20250No source
Nov 20250No source
Dec 20250No source
Jan 20260No source
Feb 20260No source
Mar 20260No source
Apr 20260No source
May 20260No source
Jun 20260No source
Jul 20260No source
Aug 20260No source
Sep 20260No source
Oct 20260No source
Nov 20260No source

Discharge events per year, 2016 to 2026

29 events, 2016 to 2026.

  • Combined sewer overflow
  • Sanitary sewer overflow
  • Bypass, blended or other
  • No source
  • Partly covered or sparse source
No source

No source covers 2026. NH permittees publish on their own pages; each discharger's record begins on a different date.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2016-01-10 to 2025-09-30.

Show table
Discharge events per year, 2016 to 2026
YearCombined sewer overflowSanitary sewer overflowBypass, blended or otherTotalCoverage
20161203Partly covered or sparse source
20171102
20187209
20194509
20200202
20210000
20220101
20231102
20240000
20250101Partly covered or sparse source
20260000No source

Reported volume per year

Gallons, summed from the 24 events that gave a number (5 did not).

  • No source
  • Partly covered or sparse source
No source

No source covers 2026. 5 of 29 events gave no volume as a number (1 gave a range); only numbers are summed.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2016-01-10 to 2025-09-30.

Show table
Reported volume per year
YearGallonsEvents with a numberEvents withoutCoverage
201624,49330Partly covered or sparse source
2017718,26020
20182,599,56590
20191,363,51272
20206511
2021000
2022001
202314,17220
2024000
2025001Partly covered or sparse source
2026000No source

Hours under advisory per year

Hours under advisory each year; 2026 to date.

  • Advisory in effect
  • No source
  • Partly covered or sparse source
No source

No source covers 2026. 26 discharge events have no reported end and no ongoing status; under the status rules they set caution, not an advisory, and add no hours here. Official beach and cyanobacteria advisories are counted on water pages only.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2016-01-10 to 2025-09-30.

Show table
Hours under advisory per year
YearHours under advisoryShare of the yearCoverage
201600.0%Partly covered or sparse source
20171201.4%
201800.0%
20191201.4%
202000.0%
202100.0%
202200.0%
2023720.8%
202400.0%
202500.0%Partly covered or sparse source
202600.0%No source

Share of the May to October season under advisory

Share of the hours from May 1 to October 31 with an advisory in effect.

  • Advisory in effect
  • Season partly covered

Seasons only partly covered by a source: 2025 (share is of the covered hours). 26 discharge events have no reported end and no ongoing status; under the status rules they set caution, not an advisory, and add no hours here. Official beach and cyanobacteria advisories are counted on water pages only.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2016-01-10 to 2025-09-30.

Show table
Share of the May to October season under advisory
SeasonShare under advisoryHours under advisoryHours coveredSeason hoursPartly covered
20160.0%04,4164,416
20170.0%04,4164,416
20180.0%04,4164,416
20190.0%04,4164,416
20200.0%04,4164,416
20210.0%04,4164,416
20220.0%04,4164,416
20230.0%04,4164,416
20240.0%04,4164,416
20250.0%03,6484,416yes

Discharge events by calendar month, all years

Every counted discharge event, by the calendar month it began.

Months are summed over every year a source covers; the table gives the number of years behind each month.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2016-01-10 to 2025-09-30.

Show table
Discharge events by calendar month, all years
MonthEventsYears of records
Jan210
Feb310
Mar310
Apr510
May110
Jun110
Jul210
Aug110
Sep210
Oct19
Nov69
Dec29

Discharge events by outfall

The 10 outfalls with the most events of 15, all years.

NH permittees publish on their own pages; each discharger's record begins on a different date.

Source: NH permittee notices (Nashua, Manchester, Portsmouth, Exeter). Covered 2016-01-10 to 2025-09-30.

Show table
Discharge events by outfall
OutfallEvents
003 Clemson Pond tide gate (CSO structures: Spring St, Water St)14
SSO2
Elm Street to Gilman Street. Inadvertant private sewer connection to storm drain was discovered. Use was discontinued im1
110 Front Street - Blockage in a sewer manhole1
Exeter Hospital, 5 Alumni Dr1
115 Court St1
Hilton Ave SSO1
45 Hilton Ave SSO1
Between 45-47 Hilton Ave SSO1
11 Newfields Rd, air release valve on the force main was hit during the installation causing a SSO1
Other outfalls (5)5
How these charts are counted

Discharge events are counted once: where a source publishes both public notices and verified reports (MassDEP, Vermont DEC), a discharger's month with any verified report counts its verified reports only, and other months count notices. Revisions are folded into the record they revise, and EPA copies of a state report are not counted twice. Monthly and yearly totals (Maine DEP, EPA discharge monitoring reports, Portsmouth) are shown on their own and never added to the event counts. Hours under advisory follow the map's red rules. A muted band marks periods no source covers: a gap there is missing data, not a quiet month.

  • NH permittee notices (Nashua, Manchester, Portsmouth, Exeter): 2016-01-10 to 2025-09-30