Connecticut / Events /

Sanitary sewer overflow: GREENWICH (GRASS ISLAND WPCF), Sep 13, 2026

Ended (as reported) · GREENWICH (GRASS ISLAND WPCF) (CT DEEP Performance Dashboard)

Source: GREENWICH (GRASS ISLAND WPCF) (CT DEEP Performance Dashboard) via CT DEEP CSO/SSO Performance Dashboard (QScend), record 11469, the source gives no report time, retrieved 2026-11-02 11:20 UTC · notice

1. The reported outfall

Outfall reported by GREENWICH (GRASS ISLAND WPCF) (CT0100234): “Manhole, S Water St, Greenwich, CT”. Location: no coordinates in the record or the outfall registry.

2. Waters named in the notice

The notice names: “Into catch basins that outfall to the Byram River”. Not placed on a tracked water.

3. Modeled downstream reach

Not modeled: the reach model runs on rivers above the head of tide only.

When: three different times

The time of the event, the time the source reported, published or updated it, and the time we fetched it are kept apart. Times are shown in New England time; the record keeps the original offsets.

Started

Sep 13, 2026, 9:30 AM EDT

Ended

Sep 13, 2026, 3:00 PM EDT

Precision

Known to the minute

Reported to the source

not given

Published

not given

Source last updated

not given

We fetched it

2026-11-02 11:20 UTC

What and how much

Type

Sanitary sewer overflow

Status in the record

Ended (as reported)

Material

“Raw Sewage”

Volume

“Approximately 15 gallons per minute per manhole structure (estimated). Based on this we estimated a total of approximately 29,700 gallons that may have discharged to the surface.” (estimated)

Volume in the source's words

“Approximately 15 gallons per minute per manhole structure (estimated). Based on this we estimated a total of approximately 29,700 gallons that may have discharged to the surface.”

Advice

The record carries no advice text from GREENWICH (GRASS ISLAND WPCF) (CT DEEP Performance Dashboard).

Advice window

not stated in the record; the state's window on the methods page applies

Basis

not stated

Source and revisions

Source

CT DEEP CSO/SSO Performance Dashboard (QScend)

Record id at the source

11469

Original notice

https://deepct.qscend.mygovcenter.com/cms/cms?id=1

Revision of

none (first record)

Revised by

no later revision

{
  "Reporting Utility": "GREENWICH (GRASS ISLAND WPCF)",
  "Status": "Closed",
  "Incident Type": "Sewage Bypass",
  "Weather Conditions": "Rain 1-2\" per hour",
  "Date Bypass Began or was Discovered": "09/13/2026",
  "Event Start Time": "09:30 AM",
  "Location of Bypass": "Manhole",
  "Type of Bypass": "Raw Sewage",
  "Cause of Bypass": "Excessive Flows - Storm Event",
  "Cause of Bypass Other Explanation": "Significant rainfall event in a fairly short duration (over 4-inches of rain recorded)",
  "How was Incident Discovered": "Visually observed while staff responded to storm event.  Portions of the road were underwater.",
  "Estimated Quantity or Rate of Discharge": "Approximately 15 gallons per minute per manhole structure (estimated).",
  "How was estimated Quantity or Rate Determined": "Based on visual observations",
  "Reach Waterbody": "Yes",
  "Request ID": "11469",
  "Waterbody Name": "Into catch basins that outfall to the Byram River",
  "Date Bypass Ended": "09/13/2026",
  "Event End Time": "03:00 PM",
  "Final Quantity": "Approximately 15 gallons per minute per manhole structure (estimated).  Based on this we estimated a total of approximately 29,700 gallons that may have discharged to the surface.",
  "How was Final Volume Determined": null,
  "How incident was resolved": "Rain subsided and collection system was able to catch up",
  "Municipality": "Greenwich",
  "Address": "S Water St, Greenwich, CT",
  "_view": "SSO DATA VIEW",
  "_dww_note": [
    "receiving water 'Into catch basins that outfall to the Byram River' has no matching water record"
  ]
}