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New Hampshire · EPA ECHO (national)
PORTSMOUTH-PIERCE ISLAND SANITARY SEWER SYSTEM
Permit NH0100234
—
No waterway impact reported
Reported events
2
Total volume
11 gal
Reached waterways
0 (0%)
Reporting since
2025
What caused the overflows
Grease / FOG
1
Other / Unknown
1
Reported overflow events (showing 2 of 2)
| Date | Volume | Cause | Reached water | Receiving water |
|---|---|---|---|---|
| Mar 8, 2026 | 1 gal | Other / Unknown | — | — |
| Dec 30, 2025 | 10 gal | Grease / FOG | — | South Mill Pond via the MS4 System |
Source: EPA ECHO (national). Volumes are utility-reported estimates. Some events lack precise coordinates or volumes.