New Hampshire / Reports /
New Hampshire sewage discharges in 2020
50 records of sewage discharges and water advisories in New Hampshire dated in 2020, newest first. Each record keeps the source's own times and wording; a record from the last six months, or one still in effect, also has a page of its own.
By type: Combined sewer overflow (CSO)47 · Sanitary sewer overflow (SSO)2 · Treatment plant bypass1
By source: City of Nashua Wastewater Department (History of CSO Occurrences PDF)36 · City of Portsmouth DPW (CSO page, monthly summary table)11 · Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page)3
2020 in other states: Connecticut, Maine, New York, Pennsylvania, Rhode Island, Vermont.
Source: the agencies, sewer operators and EPA records named on each row and on the Sources page. Updated 2026-11-02 21:26 UTC.
| Start | Type | Water | Sewer operator | Outlet | Volume | Status and end | Source and record |
|---|---|---|---|---|---|---|---|
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 42,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-12-25:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Sanitary sewer overflow (SSO) | not linked to a mapped water | Town of Exeter DPW | 115 Court St | 65 gallons | Ended (as reported); end time not reported | Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via History of CSO Occurrences PDF, record exeter:sso:2020-12-17:1, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 7,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-12-12:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 15,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-12-05:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10A Parrot Avenue | 3,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-12:10A, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 003 Farmington Rd. | 300 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-11-30:003, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 5,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-11-30:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 1,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-11-26:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 3,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-11-23:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 1,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-11-15:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10A Parrot Avenue | 40,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-11:10A, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 15,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-10-17:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 28,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-10-13:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 009 Lock St. | 1,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-10-13:009, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10A Parrot Avenue | 9,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-10:10A, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 2,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-09-28:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 003 Farmington Rd. | 19,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-09-10:003, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 004 Burke St. | 1.89 million gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-09-10:004, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 006 Nashua River | 1.88 million gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-09-10:006, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 2,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-09-10:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 014 Bridge St. | 3.92 million gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-09-10:014, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10A Parrot Avenue | 5,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-09:10A, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 005 East Hollis St. | 4,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-08-29:005, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 19,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-08-29:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 003 Farmington Rd. | 6,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-08-17:003, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10A Parrot Avenue | 2,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-08:10A, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 15,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-07-23:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 005 East Hollis St. | 36,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-07-22:005, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 39,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-07-22:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 005 East Hollis St. | 5,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-07-01:005, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10A Parrot Avenue | 40,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-07:10A, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10B Parrot Avenue | 3,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-07:10B, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 003 Farmington Rd. | 5,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-06-24:003, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 005 East Hollis St. | 16,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-06-24:005, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 5,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-06-24:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10A Parrot Avenue | 372,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-06:10A, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10B Parrot Avenue | 117,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-06:10B, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Piscataqua River | City of Portsmouth DPW Wastewater Division | 013 Deer Street | 319,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-06:013, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 003 Farmington Rd. | 12,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-05-15:003, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 1,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-05-15:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Treatment plant bypass | Squamscott River | Town of Exeter WWTP | 001 WWTP outfall 001 | 800,000 gallons | Ended (as reported); Apr 21, 2020 | Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via History of CSO Occurrences PDF, record exeter:bypass:2020-04-20:1, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 7,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-03-29:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Sanitary sewer overflow (SSO) | not linked to a mapped water | Town of Exeter DPW | Hilton Ave SSO | volume not reported | Ended (as reported); end time not reported | Town of Exeter DPW (Combined Sewer & Sanitary Sewer Overflows page) via History of CSO Occurrences PDF, record exeter:sso:2020-02-28:1, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 003 Farmington Rd. | 10,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-01-25:003, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 004 Burke St. | 240,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-01-25:004, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 005 East Hollis St. | 133,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-01-25:005, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 006 Nashua River | 163,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-01-25:006, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Nashua River | City of Nashua Wastewater Department | 008 Broad St. | 16,000 gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-01-25:008, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Merrimack River | City of Nashua Wastewater Department | 014 Bridge St. | 2.8 million gallons | Ended (as reported); end time not reported | City of Nashua Wastewater Department (History of CSO Occurrences PDF), record nashua:2020-01-25:014, the source gives no report time, retrieved 2026-11-02 15:54 UTC · Original notice · Full record | |
| Combined sewer overflow (CSO) | Portsmouth Harbor | City of Portsmouth DPW Wastewater Division | 10A Parrot Avenue | 6,000 gallons | Ended (as reported); end time not reported | City of Portsmouth DPW (CSO page, monthly summary table) via History of CSO Occurrences PDF, record portsmouth:2020-01:10A, the source gives no report time, retrieved 2026-11-02 21:19 UTC · Original notice · Full record |