City of Somerville DPW
CSO · Massachusetts · Somerville
- NPDES permit
- MA0101982
- Outfalls
- 2 with coordinates in the registry (the state's layer lists 1)
- Receiving waters
- ALEWIFE BROOK; MYSTIC RIVER
- Tracked waters
- Mystic River, MA
- Events tracked
- 57 discharges · latest Oct 11, 2026, 11:02 PM EDT
- Volume reported
- 86,016,000 gallons across the 56 discharges that give a volume (1 without one)
Source: discharger record from the project's research and EPA ECHO (dischargers.json); counts from the 57 event records below, as of 2026-11-02 11:56 UTC.
How it tells the public
Somerville https://www.somervillema.gov/cso ('Subscribe to Somerville CSO and SSO Activation & Discharge Notifications'); Aquasight/ADS map lists a Somerville community. MassDEP portal: 131 rows, latest 2026-10-11.
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.
2 outfalls in the registry
- 001A 100 FT BEYOND END OF MATIGNON RD · CSO · Little River · not on a tracked water
- 007A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 · TCS · Mystic River
Source: EPA ECHO CSO outfall inventory matched to waters (data/outfalls-ne.json).
Event history
| Start | End | Water | Outfall | Type | Volume | Source | Links |
|---|---|---|---|---|---|---|---|
| Oct 11, 2026, 11:02 PM EDT | ended, time not reported | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 9f9cd5fd-1531-474f-bf92-62ae79451d8b, published Oct 12, 2026, 12:06 PM EDT, retrieved 2026-11-02 11:54 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Oct 11, 2026, 11:02 PM EDT · Map |
| Sep 27, 2026, 10:45 AM EDT | Sep 27, 2026, 2:30 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 1.09 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 0fd214b4-b1ad-4423-895c-3582894da7d4, published Oct 8, 2026, 4:04 PM EDT, retrieved 2026-11-02 11:54 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Sep 27, 2026, 10:45 AM EDT · Map |
| Sep 27, 2026, 10:30 AM EDT | Sep 27, 2026, 2:30 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 00ba4dd7-d5a3-4ade-a69d-eb5d4e9413df, published Sep 27, 2026, 9:21 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Sep 27, 2026, 10:30 AM EDT · Map |
| Jul 30, 2026, 12:59 AM EDT | Jul 30, 2026, 1:18 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 60,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record d7d46d3c-4520-4291-9730-81b78f15dbc3, published Aug 5, 2026, 2:16 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 30, 2026, 12:59 AM EDT · Map |
| Jul 30, 2026, 12:59 AM EDT | Jul 30, 2026, 1:18 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 78d7560c-7e80-44ae-ae79-36f25cc8d45a, published Jul 30, 2026, 6:23 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 30, 2026, 12:59 AM EDT · Map |
| Jul 22, 2026, 5:05 PM EDT | Jul 22, 2026, 5:40 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 71485eac-5c92-4495-ae11-841df1512520, published Jul 22, 2026, 7:24 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 22, 2026, 5:05 PM EDT · Map |
| Jul 22, 2026, 4:45 PM EDT | Jul 22, 2026, 5:40 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 1.61 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 8fa65d5c-7c7e-49cc-8cdc-6fd6b8abc654, published Aug 5, 2026, 2:25 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 22, 2026, 4:45 PM EDT · Map |
| Jul 22, 2026, 4:25 PM EDT | Jul 22, 2026, 4:35 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 106,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 0f673e83-57ac-45ad-b3e8-bd26684be44f, published Aug 13, 2026, 9:02 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 22, 2026, 4:25 PM EDT · Map |
| Jul 22, 2026, 4:25 PM EDT | Jul 22, 2026, 4:35 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record e939f5ef-7910-4bd9-9b77-9f70ed3591fb, published Jul 24, 2026, 2:08 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 22, 2026, 4:25 PM EDT · Map |
| Jul 21, 2026, 8:45 PM EDT | Jul 21, 2026, 9:00 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 290,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 9bcfc5f3-d151-49f6-8238-91ec5c1374de, published Aug 5, 2026, 2:22 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 21, 2026, 8:45 PM EDT · Map |
| Jul 21, 2026, 8:41 PM EDT | Jul 21, 2026, 9:00 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record c3b7c085-68ed-4787-a210-d497bc0bb01d, published Jul 22, 2026, 6:26 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 21, 2026, 8:41 PM EDT · Map |
| Jul 7, 2026, 6:30 PM EDT | Jul 7, 2026, 8:00 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 1.84 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record f8e575c0-ca41-40dd-a1b5-a915624c13e2, published Aug 5, 2026, 2:18 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 7, 2026, 6:30 PM EDT · Map |
| Jul 7, 2026, 6:30 PM EDT | Jul 7, 2026, 8:00 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 0f8d5954-34f1-48ae-bdc4-70bb48b8fd20, published Jul 8, 2026, 9:59 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 7, 2026, 6:30 PM EDT · Map |
| Jul 4, 2026, 7:10 PM EDT | Jul 4, 2026, 7:15 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 17,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 2d46e54f-ef0c-4cba-9aba-45c24eef7b04, published Aug 13, 2026, 8:59 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 4, 2026, 7:10 PM EDT · Map |
| Jul 4, 2026, 7:10 PM EDT | Jul 4, 2026, 7:15 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 39671202-33c8-4a50-be42-cd3b68682954, published Jul 4, 2026, 9:00 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | Event: Combined sewer overflow, CITY OF SOMERVILLE, Jul 4, 2026, 7:10 PM EDT · Map |
| Oct 13, 2025, 4:09 PM EDT | Oct 13, 2025, 6:15 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 53de697b-4c6c-47e4-a6e1-1ce87d05c00f, published Oct 14, 2025, 8:13 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Oct 13, 2025, 4:00 PM EDT | Oct 13, 2025, 6:15 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 590,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 4d637f83-2105-4c23-bd37-b4a8a8d3f59f, published Nov 12, 2025, 9:31 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Oct 8, 2025, 10:30 AM EDT | Oct 8, 2025, 10:45 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 40,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 08adc1c7-dd73-4487-9c2e-28b58120e6f0, published Nov 12, 2025, 8:43 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Oct 8, 2025, 10:25 AM EDT | Oct 8, 2025, 10:45 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 6b1b25dd-c6fd-4b93-997b-abce5c9af848, published Oct 8, 2025, 3:54 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Oct 8, 2025, 8:55 AM EDT | Oct 8, 2025, 9:35 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 729,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record a205351b-6299-4610-b856-0cb47a09717c, published Oct 14, 2025, 11:30 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Oct 8, 2025, 8:55 AM EDT | Oct 8, 2025, 9:35 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 7a32b536-dab0-48fd-a723-8a33a13fe73c, published Oct 8, 2025, 3:50 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 7, 2025, 6:10 PM EDT | Sep 7, 2025, 6:25 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 388,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record d897f827-f041-49b3-993a-aef2bcc3e357, published Oct 14, 2025, 8:24 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Aug 29, 2025, 3:00 PM EDT | Aug 29, 2025, 3:10 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 39,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record ac8add68-079f-4c34-897c-2a3afa54e950, published Oct 14, 2025, 8:33 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Aug 29, 2025, 3:00 PM EDT | Aug 29, 2025, 3:10 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record b27773c4-2a72-4956-923b-75e773a8491d, published Aug 30, 2025, 8:12 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| May 22, 2025, 7:00 PM EDT | May 22, 2025, 11:20 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 7.33 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 4a16134f-f38e-46a8-a6ea-8994b871e321, published Jun 9, 2025, 2:17 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| May 22, 2025, 7:00 PM EDT | May 22, 2025, 11:20 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 834669c4-e87d-4c6d-93a1-c7a43185191a, published May 23, 2025, 10:13 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Mar 17, 2025, 4:35 AM EDT | Mar 17, 2025, 4:45 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 50,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 1a098a06-611a-43c0-9cbb-2f579a233c35, published Apr 8, 2025, 9:48 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Mar 17, 2025, 4:31 AM EDT | Mar 17, 2025, 4:45 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 6a313f62-7279-4f3f-9340-5566bb7a17c9, published Mar 17, 2025, 4:35 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Mar 6, 2025, 4:30 AM EST | Mar 6, 2025, 4:45 AM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 370,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 2de293fc-07b8-4451-bb96-d0f2ae4328b4, published Apr 8, 2025, 9:43 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Mar 6, 2025, 4:16 AM EST | Mar 6, 2025, 4:45 AM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 98bf7a77-e77a-4c8d-9b29-7b78d74133a9, published Mar 6, 2025, 9:42 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 11, 2024, 6:20 PM EST | Dec 11, 2024, 10:15 PM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record eb027501-f5aa-4e0c-87ed-846e027354cd, published Dec 12, 2024, 6:54 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 11, 2024, 6:10 PM EST | Dec 11, 2024, 10:15 PM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 6.36 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 988db6ea-ee79-47e2-b0e4-58eb1f535335, published Jan 14, 2025, 11:01 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 31, 2024, 11:50 AM EDT | Jul 31, 2024, 12:05 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 104,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record b4682fff-9d6c-497e-95e0-1d65bdb9715f, published Aug 16, 2024, 8:11 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 31, 2024, 11:50 AM EDT | Jul 31, 2024, 12:05 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 9581a219-a113-445f-854e-0e51bd9fa8be, published Aug 1, 2024, 10:27 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 27, 2024, 12:15 AM EDT | Jun 27, 2024, 12:20 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 26,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 9e94ff6b-d916-4819-97ed-0801561d7368, published Jul 12, 2024, 9:51 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 27, 2024, 12:15 AM EDT | Jun 27, 2024, 12:20 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record b05c7762-45b8-495c-ba4e-57c240d1602b, published Jun 28, 2024, 8:43 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 20, 2024, 9:40 PM EDT | Jun 20, 2024, 9:45 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 26,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 218f1af5-52de-4041-8f5f-a3383dc42e8e, published Jul 12, 2024, 9:45 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 20, 2024, 9:40 PM EDT | Jun 20, 2024, 9:45 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 4a7cb712-5318-493d-8de9-330685cd0615, published Jun 21, 2024, 2:00 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 14, 2024, 1:35 PM EDT | Jun 14, 2024, 2:05 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 396,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record d5e8de66-4a35-4faa-9d96-b7760b060abc, published Jul 12, 2024, 9:43 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 14, 2024, 1:35 PM EDT | Jun 14, 2024, 2:05 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 4525dcce-aa6b-40e6-a0b0-fd3bdea78b7b, published Jun 21, 2024, 2:02 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| May 30, 2024, 9:25 AM EDT | May 30, 2024, 10:05 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 290,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 41685791-a6c0-44d7-9330-77b3f252a88d, published Jun 12, 2024, 9:11 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| May 30, 2024, 9:25 AM EDT | May 30, 2024, 10:05 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 4b4a7d07-84f9-49d7-a276-a7deeb091621, published May 31, 2024, 9:35 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Apr 4, 2024, 5:25 AM EDT | Apr 4, 2024, 10:38 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 2.64 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record cc065eae-bd07-4b3e-a385-ab0ae9a09030, published May 10, 2024, 2:55 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Apr 4, 2024, 5:12 AM EDT | Apr 4, 2024, 10:38 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 0e736dba-4711-413b-b7be-89e69f1c2554, published Apr 4, 2024, 4:48 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Mar 29, 2024, 12:50 AM EDT | Mar 29, 2024, 1:31 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 870,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 87b6bf02-da9f-41f2-b3a4-c3f574a11f57, published Apr 10, 2024, 1:45 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Mar 29, 2024, 12:50 AM EDT | Mar 29, 2024, 1:31 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 88942ec1-5115-41e5-9f59-2f2d06fbd4c4, published Mar 29, 2024, 9:52 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Mar 23, 2024, 9:45 PM EDT | Mar 23, 2024, 10:29 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 510,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 71e2b104-63f2-466b-bec1-1910b58639b9, published Apr 10, 2024, 1:40 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Mar 23, 2024, 9:45 PM EDT | Mar 23, 2024, 10:29 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record fb6ebc4d-caac-4a70-a7f7-724c27cdfe74, published Mar 24, 2024, 8:54 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jan 10, 2024, 3:45 AM EST | Jan 10, 2024, 5:35 AM EST | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 2.98 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 0f44496a-85f7-48a5-bff6-cef8b8e47035, published Feb 9, 2024, 12:55 PM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jan 10, 2024, 3:45 AM EST | Jan 10, 2024, 5:35 AM EST | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 4f96d9a8-ec84-4b36-b822-bcff0c5e08db, published Jan 11, 2024, 7:26 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jan 10, 2024, 12:15 AM EST | Jan 10, 2024, 9:45 AM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 3.93 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 4d6fbaac-0828-4cb4-a41f-ad07f8d644f9, published Feb 13, 2024, 10:42 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jan 10, 2024, 12:15 AM EST | Jan 10, 2024, 9:45 AM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record b24ffc26-92ee-40b2-9406-63701147d388, published Jan 10, 2024, 7:28 PM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 18, 2023, 12:25 PM EST | Dec 18, 2023, 4:35 PM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 7.68 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 409a91c1-74d6-48bd-8b79-a95315665897, published Jan 11, 2024, 10:44 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 18, 2023, 12:22 PM EST | Dec 18, 2023, 4:35 PM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record e701fdc4-ad82-4ab6-be1f-c758ba6df03c, published Dec 18, 2023, 8:42 PM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 18, 2023, 12:20 PM EST | Dec 18, 2023, 12:50 PM EST | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 227,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record aa8d6201-22f2-4b0b-92bc-8fe577c33d00, published Jan 9, 2024, 11:12 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 18, 2023, 12:20 PM EST | Dec 18, 2023, 12:50 PM EST | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 09163d0f-592a-4925-8122-d0ad14d6bab0, published Dec 19, 2023, 7:38 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 11, 2023, 7:38 AM EST | Dec 11, 2023, 9:15 AM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record ad0cd09c-590f-40b2-9e70-4ae3a2e9061a, published Dec 11, 2023, 2:56 PM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 11, 2023, 7:25 AM EST | Dec 11, 2023, 9:15 AM EST | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 1.54 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 42d30c0a-6563-4a3d-9405-d45fde604c2b, published Jan 11, 2024, 10:36 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 11, 2023, 3:00 AM EST | Dec 11, 2023, 3:20 AM EST | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 96,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record ff023a31-2417-4641-9293-161643e05eff, published Jan 9, 2024, 11:10 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Dec 11, 2023, 3:00 AM EST | Dec 11, 2023, 3:20 AM EST | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 7b3178f0-7c0c-40ff-b5eb-c465e45f6f56, published Dec 12, 2023, 8:29 AM EST, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 18, 2023, 8:30 PM EDT | Sep 18, 2023, 9:00 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 243,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record b369a2da-bb1f-403f-9e92-4553f8aaef03, published Oct 10, 2023, 8:41 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 18, 2023, 8:30 PM EDT | Sep 18, 2023, 9:00 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record fc6b62da-11ba-460d-bcce-aeab95dbff5c, published Sep 19, 2023, 10:25 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 18, 2023, 1:50 PM EDT | Sep 18, 2023, 4:40 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record c914dd9c-509a-40e6-9a7c-bd087c915fdf, published Sep 19, 2023, 4:59 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 18, 2023, 1:40 PM EDT | Sep 18, 2023, 4:40 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 2.19 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 6d73fd3d-1002-4d66-b4a8-154340facd97, published Oct 17, 2023, 10:19 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 13, 2023, 1:35 PM EDT | Sep 13, 2023, 1:45 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 35,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 0898b9b0-fe6c-4c8e-be8a-cedb6346759f, published Oct 10, 2023, 8:41 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 13, 2023, 1:35 PM EDT | Sep 13, 2023, 1:45 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record ed2bf38b-b9bb-4fd4-8aa3-dbf1ebaaa2fe, published Sep 14, 2023, 9:49 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 9, 2023, 4:20 PM EDT | Sep 9, 2023, 4:25 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 32,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record d5f2783f-38df-4dde-b07c-8f0dbb0032f7, published Oct 10, 2023, 8:40 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Sep 9, 2023, 4:20 PM EDT | Sep 9, 2023, 4:25 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 41a00c29-0310-4c01-91f9-3e82bbaeb002, published Sep 11, 2023, 9:38 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Aug 8, 2023, 11:15 AM EDT | Aug 8, 2023, 12:30 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 3.34 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record f09e1721-19b2-4b76-8718-461edd0a83f4, published Sep 12, 2023, 10:30 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Aug 8, 2023, 11:12 AM EDT | Aug 8, 2023, 12:30 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 9f537211-52f9-429a-8eb2-afe64ffe1368, published Aug 8, 2023, 6:24 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Aug 8, 2023, 10:45 AM EDT | Aug 8, 2023, 12:05 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 3.41 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 3b3d02ce-c303-4dec-8c25-ca840b6eeb68, published Sep 8, 2023, 12:55 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Aug 8, 2023, 10:45 AM EDT | Aug 8, 2023, 12:05 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 05b53457-70ac-4754-b0d9-0566985e8eff, published Aug 9, 2023, 7:23 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 29, 2023, 6:15 PM EDT | Jul 29, 2023, 6:45 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 122,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 33d144e2-f1f4-445a-94a9-df6636a126ab, published Aug 11, 2023, 2:27 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 29, 2023, 6:15 PM EDT | Jul 29, 2023, 6:45 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 1d5a430b-63ca-478e-937b-c20aba3e8131, published Jul 30, 2023, 9:20 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 29, 2023, 6:10 PM EDT | Jul 29, 2023, 11:20 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 9.95 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 05b12974-09a2-4983-b06f-c6fccaacea79, published Aug 15, 2023, 1:42 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 29, 2023, 6:06 PM EDT | Jul 29, 2023, 11:20 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record e901b706-d6f4-4393-bbdc-245d4e2f2305, published Jul 30, 2023, 7:23 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 21, 2023, 9:35 PM EDT | Jul 21, 2023, 10:25 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 5c3dacd1-3a1f-4b9d-9463-f8afee544111, published Jul 22, 2023, 7:25 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 21, 2023, 9:30 PM EDT | Jul 21, 2023, 10:25 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 1.73 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 9673c9cc-c70e-483a-8c97-0963b61aaaca, published Aug 15, 2023, 1:21 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 21, 2023, 9:20 PM EDT | Jul 21, 2023, 9:50 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 933,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 1bac58fc-11de-462e-ab93-37bb36191aea, published Aug 11, 2023, 2:26 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 21, 2023, 9:20 PM EDT | Jul 21, 2023, 9:50 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record c6330291-53b7-4003-9d9c-a5ecb69727cb, published Jul 22, 2023, 7:13 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 16, 2023, 12:05 PM EDT | Jul 16, 2023, 1:10 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 1.1 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record c3715133-7af4-4dc1-91a2-e87be224dad4, published Aug 15, 2023, 12:11 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 16, 2023, 12:05 PM EDT | Jul 16, 2023, 1:10 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 811dc9ec-7237-496d-a244-080688e1da14, published Jul 16, 2023, 10:42 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 10, 2023, 2:15 PM EDT | Jul 10, 2023, 2:45 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 370,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 6816ee18-1b21-4774-8beb-0eecf512f0bc, published Aug 11, 2023, 2:26 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 10, 2023, 2:15 PM EDT | Jul 10, 2023, 2:45 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 299bdb3c-3fb6-4f48-a76a-25c8767e1cd7, published Jul 11, 2023, 8:21 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 3, 2023, 2:05 AM EDT | Jul 3, 2023, 2:20 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 120,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 784f69b5-1585-4e29-b81c-ce336b17e2bb, published Aug 15, 2023, 11:48 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 3, 2023, 2:05 AM EDT | Jul 3, 2023, 2:20 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 318820b3-8eab-4f63-8bfd-9ec368baabc9, published Jul 10, 2023, 9:46 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 3, 2023, 1:45 AM EDT | Jul 3, 2023, 2:15 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 374,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 7fbd8ccc-cc1f-427d-83b2-33e7672fd3a4, published Aug 11, 2023, 2:19 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jul 3, 2023, 1:45 AM EDT | Jul 3, 2023, 2:15 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 90b157c4-8e5d-4fd8-aaaf-b6a15fbe0508, published Jul 3, 2023, 11:23 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 14, 2023, 8:20 PM EDT | Jun 14, 2023, 9:10 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 260,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record c02eca54-11bd-4cc5-9560-010c9b4b0676, published Jul 7, 2023, 12:55 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 14, 2023, 8:05 PM EDT | Jun 14, 2023, 9:10 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 840cdc06-206f-4a1f-8539-4ed0f0c7b308, published Jun 15, 2023, 7:28 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 10, 2023, 3:00 PM EDT | Jun 10, 2023, 3:00 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record df28f89c-91a4-4248-9550-866372ce38aa, published Jun 10, 2023, 9:29 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 10, 2023, 2:50 PM EDT | Jun 10, 2023, 3:00 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 30,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record c1d68afb-c174-40a5-b991-cec721078222, published Jul 7, 2023, 12:49 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 10, 2023, 2:25 PM EDT | Jun 10, 2023, 3:25 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 216,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record ae81afc8-f0e8-4b04-9e11-0572e263b45f, published Jul 14, 2023, 2:36 PM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Jun 10, 2023, 2:25 PM EDT | Jun 10, 2023, 3:25 PM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 27816217-705d-49c9-b2e2-2b0b12589a8e, published Jun 12, 2023, 11:37 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| May 20, 2023, 11:45 PM EDT | May 21, 2023, 2:45 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 6 million gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 90da77d2-d37e-423c-8073-54f1a4c1e3b3, published Jun 13, 2023, 8:55 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| May 20, 2023, 11:45 PM EDT | May 21, 2023, 2:45 AM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 6ce49223-9323-4e21-b913-59be1d896659, published May 21, 2023, 8:35 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| May 20, 2023, 11:25 PM EDT | May 21, 2023, 12:20 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflow | 961,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record d3212fc9-552e-4d4e-aadb-bca44873db82, published Jun 12, 2023, 10:07 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| May 20, 2023, 11:25 PM EDT | May 21, 2023, 12:20 AM EDT | “ALEWIFE BROOK” (not placed) | SOM001A 100 FT BEYOND END OF MATIGNON RD | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 6b1e334c-c9d4-4953-907e-c7b2bdd9fb74, published May 22, 2023, 9:58 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Apr 30, 2023, 11:20 PM EDT | Apr 30, 2023, 11:55 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflow | 390,000 gal | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record b2962f88-662d-45ad-b79c-4e598a9889fd, published May 11, 2023, 11:44 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
| Apr 30, 2023, 11:20 PM EDT | Apr 30, 2023, 11:55 PM EDT | Mystic River, MA | SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | Combined sewer overflowrevised | not reported | CITY OF SOMERVILLE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal (eeaonline.eea.state.ma.us/dep/CSOAPI/api/), record 6490a2be-0315-4259-9959-ad1db5993339, published May 1, 2023, 7:08 AM EDT, retrieved 2026-11-02 10:58 UTC · notice | record below · Map |
Full record (older than 180 days, so no page of its own) | |||||||
Showing the newest 100 events of 112 events. See them all with filters.
History
- Discharge events, last 12 months8Dec 2025 to Nov 2026
- Days with a discharge, last 12 months7Dec 2025 to Nov 2026
- Hours under advisory, last 12 months267Dec 2025 to Nov 2026; on this discharger's reports
- 2026 season under advisory6.0%May to October; 267 h
Discharge events per month
57 events, Jan 2022 to Nov 2026. Counted from 56 verified or annual reports, 1 public notices.
- Combined sewer overflow
- Sanitary sewer overflow
- Bypass, blended or other
- No source
- Partly covered or sparse source
No source covers 2022-01 to 2022-05. MassDEP portal records begin 2022-06-30. Verified Data Reports arrive after the month ends, so the latest months count public notices.
Source: MassDEP sewage notification portal. Covered 2022-06-30 to 2026-11-02.
Show table
| Month | Combined sewer overflow | Sanitary sewer overflow | Bypass, blended or other | Total | Counted from | Coverage |
|---|---|---|---|---|---|---|
| Jan 2022 | 0 | 0 | 0 | 0 | No source | |
| Feb 2022 | 0 | 0 | 0 | 0 | No source | |
| Mar 2022 | 0 | 0 | 0 | 0 | No source | |
| Apr 2022 | 0 | 0 | 0 | 0 | No source | |
| May 2022 | 0 | 0 | 0 | 0 | No source | |
| Jun 2022 | 0 | 0 | 0 | 0 | Partly covered or sparse source | |
| Jul 2022 | 0 | 0 | 0 | 0 | ||
| Aug 2022 | 0 | 0 | 0 | 0 | ||
| Sep 2022 | 0 | 0 | 0 | 0 | ||
| Oct 2022 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Nov 2022 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Dec 2022 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Jan 2023 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Feb 2023 | 0 | 0 | 0 | 0 | ||
| Mar 2023 | 2 | 0 | 0 | 2 | Verified or annual reports | |
| Apr 2023 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| May 2023 | 2 | 0 | 0 | 2 | Verified or annual reports | |
| Jun 2023 | 3 | 0 | 0 | 3 | Verified or annual reports | |
| Jul 2023 | 8 | 0 | 0 | 8 | Verified or annual reports | |
| Aug 2023 | 2 | 0 | 0 | 2 | Verified or annual reports | |
| Sep 2023 | 4 | 0 | 0 | 4 | Verified or annual reports | |
| Oct 2023 | 0 | 0 | 0 | 0 | ||
| Nov 2023 | 0 | 0 | 0 | 0 | ||
| Dec 2023 | 4 | 0 | 0 | 4 | Verified or annual reports | |
| Jan 2024 | 2 | 0 | 0 | 2 | Verified or annual reports | |
| Feb 2024 | 0 | 0 | 0 | 0 | ||
| Mar 2024 | 2 | 0 | 0 | 2 | Verified or annual reports | |
| Apr 2024 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| May 2024 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Jun 2024 | 3 | 0 | 0 | 3 | Verified or annual reports | |
| Jul 2024 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Aug 2024 | 0 | 0 | 0 | 0 | ||
| Sep 2024 | 0 | 0 | 0 | 0 | ||
| Oct 2024 | 0 | 0 | 0 | 0 | ||
| Nov 2024 | 0 | 0 | 0 | 0 | ||
| Dec 2024 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Jan 2025 | 0 | 0 | 0 | 0 | ||
| Feb 2025 | 0 | 0 | 0 | 0 | ||
| Mar 2025 | 2 | 0 | 0 | 2 | Verified or annual reports | |
| Apr 2025 | 0 | 0 | 0 | 0 | ||
| May 2025 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Jun 2025 | 0 | 0 | 0 | 0 | ||
| Jul 2025 | 0 | 0 | 0 | 0 | ||
| Aug 2025 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Sep 2025 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Oct 2025 | 3 | 0 | 0 | 3 | Verified or annual reports | |
| Nov 2025 | 0 | 0 | 0 | 0 | ||
| Dec 2025 | 0 | 0 | 0 | 0 | ||
| Jan 2026 | 0 | 0 | 0 | 0 | ||
| Feb 2026 | 0 | 0 | 0 | 0 | ||
| Mar 2026 | 0 | 0 | 0 | 0 | ||
| Apr 2026 | 0 | 0 | 0 | 0 | ||
| May 2026 | 0 | 0 | 0 | 0 | ||
| Jun 2026 | 0 | 0 | 0 | 0 | ||
| Jul 2026 | 6 | 0 | 0 | 6 | Verified or annual reports | |
| Aug 2026 | 0 | 0 | 0 | 0 | ||
| Sep 2026 | 1 | 0 | 0 | 1 | Verified or annual reports | |
| Oct 2026 | 1 | 0 | 0 | 1 | Public notices (no report yet) | |
| Nov 2026 | 0 | 0 | 0 | 0 |
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 source covers 2022-01 to 2022-05. 1 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. MassDEP portal records begin 2022-06-30. Verified Data Reports arrive after the month ends, so the latest months count public notices.
Source: MassDEP sewage notification portal. Covered 2022-06-30 to 2026-11-02.
Show table
| Month | Hours under advisory | From discharge windows | Hours in month | Coverage |
|---|---|---|---|---|
| Jan 2022 | 0 | 0 | 744 | No source |
| Feb 2022 | 0 | 0 | 672 | No source |
| Mar 2022 | 0 | 0 | 744 | No source |
| Apr 2022 | 0 | 0 | 720 | No source |
| May 2022 | 0 | 0 | 744 | No source |
| Jun 2022 | 0 | 0 | 720 | Partly covered or sparse source |
| Jul 2022 | 0 | 0 | 744 | |
| Aug 2022 | 0 | 0 | 744 | |
| Sep 2022 | 0 | 0 | 720 | |
| Oct 2022 | 48 | 48 | 744 | |
| Nov 2022 | 5 | 5 | 720 | |
| Dec 2022 | 95 | 95 | 744 | |
| Jan 2023 | 51 | 51 | 744 | |
| Feb 2023 | 0 | 0 | 672 | |
| Mar 2023 | 102 | 102 | 744 | |
| Apr 2023 | 1 | 1 | 720 | |
| May 2023 | 99 | 99 | 744 | |
| Jun 2023 | 98 | 98 | 720 | |
| Jul 2023 | 248 | 248 | 744 | |
| Aug 2023 | 50 | 50 | 744 | |
| Sep 2023 | 152 | 152 | 720 | |
| Oct 2023 | 0 | 0 | 744 | |
| Nov 2023 | 0 | 0 | 720 | |
| Dec 2023 | 107 | 107 | 744 | |
| Jan 2024 | 58 | 58 | 744 | |
| Feb 2024 | 0 | 0 | 696 | |
| Mar 2024 | 97 | 97 | 744 | |
| Apr 2024 | 53 | 53 | 720 | |
| May 2024 | 39 | 39 | 744 | |
| Jun 2024 | 155 | 155 | 720 | |
| Jul 2024 | 12 | 12 | 744 | |
| Aug 2024 | 36 | 36 | 744 | |
| Sep 2024 | 0 | 0 | 720 | |
| Oct 2024 | 0 | 0 | 744 | |
| Nov 2024 | 0 | 0 | 720 | |
| Dec 2024 | 52 | 52 | 744 | |
| Jan 2025 | 0 | 0 | 744 | |
| Feb 2025 | 0 | 0 | 672 | |
| Mar 2025 | 96 | 96 | 744 | |
| Apr 2025 | 0 | 0 | 720 | |
| May 2025 | 52 | 52 | 744 | |
| Jun 2025 | 0 | 0 | 720 | |
| Jul 2025 | 0 | 0 | 744 | |
| Aug 2025 | 48 | 48 | 744 | |
| Sep 2025 | 48 | 48 | 720 | |
| Oct 2025 | 100 | 100 | 744 | |
| Nov 2025 | 0 | 0 | 720 | |
| Dec 2025 | 0 | 0 | 744 | |
| Jan 2026 | 0 | 0 | 744 | |
| Feb 2026 | 0 | 0 | 672 | |
| Mar 2026 | 0 | 0 | 744 | |
| Apr 2026 | 0 | 0 | 720 | |
| May 2026 | 0 | 0 | 744 | |
| Jun 2026 | 0 | 0 | 720 | |
| Jul 2026 | 214 | 214 | 744 | |
| Aug 2026 | 1 | 1 | 744 | |
| Sep 2026 | 52 | 52 | 720 | |
| Oct 2026 | 0 | 0 | 744 | |
| Nov 2026 | 0 | 0 | 32 |
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 source covers 2022-01 to 2022-05.
Source: MassDEP sewage notification portal. Covered 2022-06-30 to 2026-11-02.
Show table
| Month | Days with a discharge | Coverage |
|---|---|---|
| Jan 2022 | 0 | No source |
| Feb 2022 | 0 | No source |
| Mar 2022 | 0 | No source |
| Apr 2022 | 0 | No source |
| May 2022 | 0 | No source |
| Jun 2022 | 0 | Partly covered or sparse source |
| Jul 2022 | 0 | |
| Aug 2022 | 0 | |
| Sep 2022 | 0 | |
| Oct 2022 | 1 | |
| Nov 2022 | 1 | |
| Dec 2022 | 1 | |
| Jan 2023 | 1 | |
| Feb 2023 | 0 | |
| Mar 2023 | 2 | |
| Apr 2023 | 1 | |
| May 2023 | 2 | |
| Jun 2023 | 2 | |
| Jul 2023 | 5 | |
| Aug 2023 | 1 | |
| Sep 2023 | 3 | |
| Oct 2023 | 0 | |
| Nov 2023 | 0 | |
| Dec 2023 | 2 | |
| Jan 2024 | 1 | |
| Feb 2024 | 0 | |
| Mar 2024 | 2 | |
| Apr 2024 | 1 | |
| May 2024 | 1 | |
| Jun 2024 | 3 | |
| Jul 2024 | 1 | |
| Aug 2024 | 0 | |
| Sep 2024 | 0 | |
| Oct 2024 | 0 | |
| Nov 2024 | 0 | |
| Dec 2024 | 1 | |
| Jan 2025 | 0 | |
| Feb 2025 | 0 | |
| Mar 2025 | 2 | |
| Apr 2025 | 0 | |
| May 2025 | 1 | |
| Jun 2025 | 0 | |
| Jul 2025 | 0 | |
| Aug 2025 | 1 | |
| Sep 2025 | 1 | |
| Oct 2025 | 2 | |
| Nov 2025 | 0 | |
| Dec 2025 | 0 | |
| Jan 2026 | 0 | |
| Feb 2026 | 0 | |
| Mar 2026 | 0 | |
| Apr 2026 | 0 | |
| May 2026 | 0 | |
| Jun 2026 | 0 | |
| Jul 2026 | 5 | |
| Aug 2026 | 0 | |
| Sep 2026 | 1 | |
| Oct 2026 | 1 | |
| Nov 2026 | 0 |
Reported volume per year
Gallons, summed from the 56 events that gave a number (1 did not).
- Partly covered or sparse source
1 of 57 events gave no volume as a number; only numbers are summed.
Source: MassDEP sewage notification portal. Covered 2022-06-30 to 2026-11-02.
Show table
| Year | Gallons | Events with a number | Events without | Coverage |
|---|---|---|---|---|
| 2022 | 2,752,000 | 3 | 0 | Partly covered or sparse source |
| 2023 | 50,579,000 | 27 | 0 | |
| 2024 | 18,136,000 | 11 | 0 | |
| 2025 | 9,536,000 | 8 | 0 | |
| 2026 | 5,013,000 | 7 | 1 |
Hours under advisory per year
Hours under advisory each year; 2026 to date.
- Advisory in effect
- Partly covered or sparse source
1 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: MassDEP sewage notification portal. Covered 2022-06-30 to 2026-11-02.
Show table
| Year | Hours under advisory | Share of the year | Coverage |
|---|---|---|---|
| 2022 | 148 | 1.7% | Partly covered or sparse source |
| 2023 | 907 | 10.3% | |
| 2024 | 502 | 5.7% | |
| 2025 | 345 | 3.9% | |
| 2026 | 267 | 3.6% |
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: MassDEP sewage notification portal. Covered 2022-06-30 to 2026-11-02.
Show table
| Month | Events | Years of records |
|---|---|---|
| Jan | 3 | 4 |
| Feb | 0 | 4 |
| Mar | 6 | 4 |
| Apr | 2 | 4 |
| May | 4 | 4 |
| Jun | 6 | 5 |
| Jul | 15 | 5 |
| Aug | 3 | 5 |
| Sep | 6 | 5 |
| Oct | 5 | 5 |
| Nov | 1 | 5 |
| Dec | 6 | 4 |
Discharge events by outfall
The 2 outfalls with the most events of 2, all years.
MassDEP portal records begin 2022-06-30. Verified Data Reports arrive after the month ends, so the latest months count public notices.
Source: MassDEP sewage notification portal. Covered 2022-06-30 to 2026-11-02.
Show table
| Outfall | Events |
|---|---|
| SOM007A/MWR205A SOUTH BANK OF MYSTIC RIVER AT INT OF ASSEMBLY SQ DR & 28 | 33 |
| SOM001A 100 FT BEYOND END OF MATIGNON RD | 24 |
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.
- MassDEP sewage notification portal: 2022-06-30 to now