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Massachusetts / Reports /

Combined sewer overflow (CSO) reported — CITY OF CAMBRIDGE, Jul 29, 2026

Ended (as reported) · CITY OF CAMBRIDGE (MassDEP sewage notification portal)

Source: CITY OF CAMBRIDGE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal, record b16b77f0-4533-4294-bd24-28883fe57ff8, published Jul 30, 2026, 9:21 AM EDT, retrieved 2026-11-02 10:58 UTC · Read the original notice

Current status from this report

Earlier version. A later record from the same source replaces this one. The newest version sets the map status. read the newer version

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1. Reported wastewater outlet

Operator named in the record: CITY OF CAMBRIDGE (federal wastewater discharge permit, NPDES, MA0101974). Outlet: CAM401A “MBTA 97 CAMBRIDGE PARK DR”. Location: 42.39565, -71.14399; location source: from the state's or EPA's outfall layer.

Outfall: a pipe or outlet where wastewater enters a water body.

2. Waters named in the notice

The notice names: “ALEWIFE BROOK”. DirtyWaterWatch links this report to Alewife Brook, MA. Match basis: the water named in the report.

3. Estimated downstream stretch

No downstream estimate is available for this report.

Map sources: water outlines and launches from OpenBoatLaunch and OpenStreetMap contributors (Open Database License); wastewater outlets from EPA and state records; downstream estimates by DirtyWaterWatch using U.S. Geological Survey maps and flow data. Base map: OpenFreeMap and OpenMapTiles.

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When it happened and when it was reported

Event and notice times use Eastern Time (EST or EDT). Retrieval times use Coordinated Universal Time (UTC).

Started
Ended
Detail provided by the source
Times known to the minute
Reported to the source
not given
Published
Source last updated
not given
Last retrieved by DirtyWaterWatch

What and how much

Type
Combined sewer overflow (CSO): sewage mixed with rainwater spills from a shared sewer system.
Status in the record
Ended (as reported)
Material
“CSO – UnTreated”
Volume
volume not reported (not stated whether estimated or measured)
Volume as reported
none

Advice from CITY OF CAMBRIDGE (MassDEP sewage notification portal)

“Avoid contact with these water bodies for 48 hours after the discharge or overflow ceases due to increased health risks from bacteria and other pollutants. See website for more information on whether specific resource areas, such as bathing beaches, are affected.”

CITY OF CAMBRIDGE (MassDEP sewage notification portal) · 314 CMR 16.04(10)(g)
Advice period
48 hours
Basis
314 CMR 16.04(10)(g)

Source and versions

Source
MassDEP CSO API behind the portal
Source record number
b16b77f0-4533-4294-bd24-28883fe57ff8
Original notice
Read the original notice
Earlier version
None: this is the first record
Later versions
version 2

Record details

Record details
Record identifierma-massdep:b16b77f0-4533-4294-bd24-28883fe57ff8
Source identifierma-massdep
Source record numberb16b77f0-4533-4294-bd24-28883fe57ff8
Earlier versionNot provided
TypeCombined sewer overflow (CSO)
Status in the reportEnded (as reported)
Sewer operator identifierma-cambridge
Sewer operatorCITY OF CAMBRIDGE
Federal wastewater discharge permit (NPDES)MA0101974
Outlet numberCAM401A
Outlet nameMBTA 97 CAMBRIDGE PARK DR
Water named in the reportALEWIFE BROOK
Linked watersalewife-brook-ma
How this report was linked to the waterthe water named in the report
Latitude42.396
Longitude-71.144
Location sourcefrom the state's or EPA's outfall layer
Location accuracy, in metresNot provided
StartedJul 29, 2026, 11:45 PM EDT (2026-07-29T23:45:00-04:00)
EndedJul 30, 2026, 12:30 AM EDT (2026-07-30T00:30:00-04:00)
Detail provided by the sourceto the minute
Reported to the sourceNot provided
PublishedJul 30, 2026, 9:21 AM EDT (2026-07-30T09:21:09-04:00)
Source last updatedNot provided
Last retrieved by DirtyWaterWatchNov 2, 2026, 5:58 AM EST (2026-11-02T10:58:11Z)
MaterialCSO – UnTreated
Volume, in gallonsNot provided
Volume as reportedNot provided
How volume was determinednot stated whether estimated or measured
AuthorityCITY OF CAMBRIDGE (MassDEP sewage notification portal)
AdviceAvoid contact with these water bodies for 48 hours after the discharge or overflow ceases due to increased health risks from bacteria and other pollutants. See website for more information on whether specific resource areas, such as bathing beaches, are affected.
Advice period, in hours48
Basis of the advice period314 CMR 16.04(10)(g)
Original noticehttps://eeaonline.eea.state.ma.us/portal/dep/cso-data-portal/details/b16b77f0-4533-4294-bd24-28883fe57ff8

Original source data

{
  "incidentId": "b16b77f0-4533-4294-bd24-28883fe57ff8",
  "incidentNumber": "26016918",
  "incidentDate": "2026-07-29T00:00:00",
  "incidentTime": "23:45",
  "amPm": null,
  "reporterClass": "Public Notification Report",
  "eventType": "CSO – UnTreated",
  "permiteeClass": "CSO",
  "permiteeName": "CITY OF CAMBRIDGE",
  "permiteeId": "MA0101974",
  "outfallId": "CAM401A",
  "municipality": "CAMBRIDGE",
  "reportingType": "Initial-Ceased",
  "location": "MBTA 97 CAMBRIDGE PARK DR",
  "latitude": null,
  "longitude": null,
  "waterBody": "ALEWIFE BROOK",
  "waterBodyDescription": null,
  "volumnOfEvent": "",
  "rainfallData": "",
  "hours": "",
  "minutes": "",
  "month": null,
  "year": null,
  "additionalInformation": null,
  "submittedDate": "2026-07-30T09:21:09.097",
  "parentIncidentId": null,
  "_report_class": "Public Notification Report",
  "_tz_assumed": "America/New_York (portal gives local clock time without zone)",
  "_ended_note": "reported ceased; the portal gives no cessation time",
  "_coords": "MassDEP CSOs layer DEP_OUTFL_ CAM401A (locations are estimates)",
  "_water": {
    "no_slug": [
      "ALEWIFE BROOK (tributary of Mystic - no slug)",
      "ALEWIFE BROOK (tributary of Mystic - no slug)"
    ]
  },
  "_advice_source": "required wording of 314 CMR 16.04(10)(g); the permittee's own advisory is only in an attachment the portal will not serve",
  "_ended_at_basis": "from Verified Data Report 26017217: its start + verified duration"
}

Source: CITY OF CAMBRIDGE (MassDEP sewage notification portal) via MassDEP CSO API behind the portal, record b16b77f0-4533-4294-bd24-28883fe57ff8, published Jul 30, 2026, 9:21 AM EDT, retrieved 2026-11-02 10:58 UTC · Read the original notice

Staff names, email addresses and phone numbers are removed from source data before it is stored.