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Connecticut / Sewer operators /

US NAVAL SUB BASE (DEPT OF NAVY)

Sewer utility · Connecticut

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.

No outlet locations are in our records for this operator. Square boat markers mark boat launches listed by OpenBoatLaunch.

Federal wastewater discharge permit (NPDES)
not recorded
Wastewater outlets
None with locations in our records
Waters listed as receiving wastewater
not recorded
Tracked waters
Thames River, CT
Discharge records counted
31 records · latest
Total reported volume in these records
1,026 gallons across the 23 records that give a volume (8 without one)

These totals reflect the records we track. Missing volumes and gaps in reporting limit comparisons between operators.

Sources: EPA ECHO and the operator and state sources linked below. Counts use the discharge records on this page. Updated 2026-11-03 14:48 UTC.

Public notices and alerts

We do not list an alert service for this operator yet. Check its website.

Source: US NAVAL SUB BASE (DEPT OF NAVY)'s public notice and alert pages and the state's notification records.

Report a missing notice or error

Wastewater outlets

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

Reports and advisories

Sanitary sewer overflow (SSO): sewage spills from a sewer meant to carry sewage separately from rainwater.

Reports linked to US NAVAL SUB BASE (DEPT OF NAVY), newest first
WhenReportStatus
to 8:00 AMWater not mapped · Lateral - Private, 1 Crystal Lake Rd, Groton, CT · SSO · “Less than 1 Gallon” report · notice · mapended
to 5:00 PMThames River · Lateral - Private, Groton, CT · SSO (earlier version) · 90 gallons in all mapended
to Aug 8 ’25, 11:59 PMThames River · Sewer Main, Military Hwy, Groton, CT · SSO (earlier version) · volume in each report mapended
to Jan 23 ’25, 8:30 AMThames River · Pump Station, 173 Dorado Rd, Groton, CT · SSO (earlier version) · 30 gallons in all mapended
to 9:30 AMWater not mapped · Sewer Main, 1 Crystal Lake Rd, Groton, CT · SSO · 5 gallons report · noticeended
to 9:00 PMWater not mapped · Manhole, 1 Crystal Lake Rd, Groton, CT · SSO · 5 gallons report · noticeended
to 3:30 AMWater not mapped · Manhole, 154 Driftwood Cir, Groton, CT · SSO · 90 gallons report · noticeended
to 9:00 AMWater not mapped · Sewer Main, 26 Highland Ave, Groton, CT · SSO · 5 gallons report · noticeended
to 1:00 PMThames River · Sewer Main, 1 Crystal Lake Rd, Groton, CT · SSO · 50 gallons report · notice · mapended
to 7:45 PMWater not mapped · Lateral - Public, 55 Hornbeam Rd, Groton, CT · SSO · 0 gallons report · noticeended
to 3:30 PMWater not mapped · Manhole, 11 Lake St, Groton, CT · SSO · 10 gallons report · noticeended
to 3:00 PMWater not mapped · Sewer Main, 1 Crystal Lake Rd, Groton, CT · SSO · 20 gallons report · noticeended
to 6:30 PMWater not mapped · Manhole, 148 Dewey Ave, Groton, CT · SSO · 10 gallons report · noticeended
to 12:30 PMWater not mapped · Manhole, Amberjack Rd, Groton, CT · SSO · 75 gallons report · noticeended
to 8:30 AMWater not mapped · Manhole, 54 Magnolia Dr, Groton, CT · SSO · 100 gallons report · noticeended
to 2:15 AMWater not mapped · Sewer Main, 26 Highland Ave, Groton, CT · SSO · 200 gallons report · noticeended
to 1:00 PMWater not mapped · Sewer Main, 1 Crystal Lake Rd, Groton, CT · SSO · 1 gallons report · noticeended
to Dec 2 ’22, 2:30 PMWater not mapped · Sewer Main, 54 Magnolia Dr, Groton, CT · SSO · “Unknown.” report · noticeended
to 2:30 AMThames River · Pump Station, 1 Crystal Lake Rd, Groton, CT · SSO · 10 gallons report · notice · mapended

Sources: CT DEEP CSO/SSO Performance Dashboard (QScend), retrieved 2026-11-02 11:20 UTC; CT DEEP Sewage Right-to-Know annual report 2024, retrieved 2026-11-03 14:32 UTC. A report's record id and times show when you hover or focus its "report" link.

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Showing the latest 25 records of 37 records.See them all with filters.

All reports in Connecticut by year: 2026 (1 from US NAVAL SUB BASE (DEPT OF NAVY)) · 2025 (9 from US NAVAL SUB BASE (DEPT OF NAVY)) · 2024 (4 from US NAVAL SUB BASE (DEPT OF NAVY)) · 2023 (9 from US NAVAL SUB BASE (DEPT OF NAVY)) · 2022 (11 from US NAVAL SUB BASE (DEPT OF NAVY)) · 2021 (3 from US NAVAL SUB BASE (DEPT OF NAVY))

Other sewer operators on these waters

The last 90 days

Last 90 days, hour by hour. Red: discharge or advisory reported. Amber: caution. Hatched amber: end not confirmed. Plum: algal bloom advisory. Red or amber with a light line inside: beach advisory or caution. Dotted: monthly report (days with discharge, dates not given). Grey: no current status on the water outline. Purple hatching: source update overdue.

No discharge, advisory or caution periods are shown for the waters this sewer operator's reports were placed on in this time span. Check downstream stretches and source coverage.

Source: DirtyWaterWatch calculations using the reports named above and the published status rules. Updated 2026-11-03 14:48 UTC.

Reported discharges over time

  • Discharges reported by US NAVAL SUB BASE (DEPT OF NAVY), last 12 months1December 2025 to November 2026Verified reports where available, else notices; revisions and duplicates counted once.
  • Days with a discharge reported by US NAVAL SUB BASE (DEPT OF NAVY), last 12 months1December 2025 to November 2026A day counts once however many discharges were under way on it. Verified reports where available, else notices; revisions and duplicates counted once.
  • Hours with a discharge or advisory status from US NAVAL SUB BASE (DEPT OF NAVY)'s reports, last 12 months48December 2025 to November 2026Red hours by the map's rules: each discharge to its reported end plus the state's post-discharge period; overlapping hours count once.
  • 2026 season with a discharge or advisory status (US NAVAL SUB BASE (DEPT OF NAVY))0.0%May to October 2026Share of May 1 to October 31 hours with red status by the map's rules, of the hours a source covered.

Combined sewer overflow (CSO): sewage mixed with rainwater spills from a shared sewer system. Sanitary sewer overflow (SSO): sewage spills from a sewer meant to carry sewage separately from rainwater. Treatment bypass: wastewater skips one or more treatment steps. Blended discharge: wastewater that skipped some treatment is mixed with treated wastewater. Outfall: a pipe or outlet where wastewater enters a water body.

Reported discharges per month

28 reported discharges, January 2022 to November 2026.

  • Combined sewer overflow
  • Sanitary sewer overflow
  • Treatment bypass, blended or other

Connecticut dashboard records begin December 2, 2021; annual-report rows that repeat a dashboard record are counted once. Connecticut's Sewage Right-to-Know annual reports cover January 1, 2021 to November 3, 2026.

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2022 to November 3, 2026.

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Hours with a discharge or advisory status per month

Hours when a water had a discharge or advisory status from this sewer operator's reports, under DirtyWaterWatch rules.

  • Discharge or advisory reported

2 discharge reports have no end time and are not marked ongoing; under DirtyWaterWatch rules they show caution, not a discharge or advisory status, and add no hours here. Official beach and cyanobacteria (harmful blue-green algae) advisories are counted on water pages only. Connecticut dashboard records begin December 2, 2021; annual-report rows that repeat a dashboard record are counted once. Connecticut's Sewage Right-to-Know annual reports cover January 1, 2021 to November 3, 2026.

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2021 to November 3, 2026.

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Days with a reported discharge per month

A day counts when any counted discharge was under way on it, from its start to its reported end in Eastern Time; a report with no end counts its start day.

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2022 to November 3, 2026.

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Reported discharges per year, 2021 to 2026

31 reported discharges, 2021 to 2026.

  • Combined sewer overflow
  • Sanitary sewer overflow
  • Treatment bypass, blended or other
  • Incomplete source coverage
Limited records

Connecticut dashboard records begin December 2, 2021; annual-report rows that repeat a dashboard record are counted once. Connecticut's Sewage Right-to-Know annual reports cover January 1, 2021 to November 3, 2026.

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2021 to November 3, 2026.

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Reported volume per year

Gallons (axis: K thousand, M million), summed from the 23 reports that gave a volume as a number (8 did not).

  • Incomplete source coverage
Limited records

8 of 31 discharge reports gave no volume as a number (4 gave a range); only numbers are summed. Some volumes in Connecticut's annual reports are given as text or ranges and are not summed.

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2021 to November 3, 2026.

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Hours with a discharge or advisory status per year

Hours with a discharge or advisory status each year under DirtyWaterWatch rules; 2026 to date.

  • Discharge or advisory reported
  • Incomplete source coverage
Limited records

2 discharge reports have no end time and are not marked ongoing; under DirtyWaterWatch rules they show caution, not a discharge or advisory status, and add no hours here. Official beach and cyanobacteria (harmful blue-green algae) advisories are counted on water pages only.

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2021 to November 3, 2026.

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Share of the May to October season with a discharge or advisory status

Share of the hours from May 1 to October 31 with a discharge or advisory status under DirtyWaterWatch rules.

  • Discharge or advisory reported

2 discharge reports have no end time and are not marked ongoing; under DirtyWaterWatch rules they show caution, not a discharge or advisory status, and add no hours here. Official beach and cyanobacteria (harmful blue-green algae) advisories are counted on water pages only.

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2021 to November 3, 2026.

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Reported discharges by calendar month, all years

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

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

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2021 to November 3, 2026.

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Reported discharges by wastewater outlet

Wastewater outlets with the most tracked discharge records: 10 of 25, all years. Counts depend on reporting coverage and do not measure legal compliance or harm.

Connecticut dashboard records begin December 2, 2021; annual-report rows that repeat a dashboard record are counted once. Connecticut's Sewage Right-to-Know annual reports cover January 1, 2021 to November 3, 2026.

Sources: Connecticut Department of Energy and Environmental Protection sewage overflow dashboard; Connecticut Sewage Right-to-Know annual reports. Records cover January 1, 2021 to November 3, 2026.

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How these charts are counted

We count each discharge once. Where a source publishes notices and confirmed reports, we use confirmed reports for an operator's month when available; otherwise we use notices. We combine revisions and exclude duplicate state reports copied by the U.S. Environmental Protection Agency (EPA). Monthly and yearly totals appear separately. Status hours follow this site's rules. Shaded gaps mean missing coverage, not zero discharges.

  • Connecticut Department of Energy and Environmental Protection sewage overflow dashboard: records from December 2, 2021 to the latest update
  • Connecticut Sewage Right-to-Know annual reports: records from January 1, 2021 to the latest update