Phillips Mill Pond Dam

Phillips Mill Pond Dam is an earth dam located in Suffolk County, New York, built in 1850. It carries a Significant hazard potential classification and has a poor condition assessment.

About Phillips Mill Pond Dam

The primary purpose of Phillips Mill Pond Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Nys Office Of Parks, Recreation & Historic Preservation- Long Island Region (state). It impounds the Nissequogue River near Smithtown.

The dam stands 10 feet tall and stretches 500 feet across, creates a reservoir covering 7 acres, and has a maximum storage capacity of 23 acre-feet. Completed in 1850, the structure is one of the older dams in the region, with over a century and a half of service.

This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. Its condition is rated poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. An emergency action plan is in place for this dam. The most recent inspection on record was 12/13/2022.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

Significant HazardPoor ConditionEmergency Action Plan: Yes

Location

StateNew York
CountySuffolk
Nearest CitySmithtown
River/StreamNissequogue River
Coordinates40.85750, -73.21389

Physical Characteristics

Dam TypeEarth
NID Height10 ft
Dam Height10 ft
Dam Length500 ft
Year Completed1850 (176 years old)

Storage & Hydraulics

NID Storage23 acre-ft
Max Storage23 acre-ft
Normal Storage14 acre-ft
Surface Area7 acres
Spillway TypeUncontrolled

Ownership & Safety

PurposeRecreation
OwnerNYS OFFICE OF PARKS, RECREATION & HISTORIC PRESERVATION- LONG ISLAND REGION
Owner TypeState
Hazard ClassificationSignificant
Condition AssessmentPoor
Last Inspection12/13/2022
Emergency Action PlanYes

Identifiers

NID IDNY14092
Federal IDNY14092
More InfoState Dam Safety Program

Nearby Dams