Upper Garden Reservoir Dam

Upper Garden Reservoir Dam is an earth dam located in Morris County, New Jersey. It carries a Significant hazard potential classification and has a satisfactory condition assessment.

About Upper Garden Reservoir Dam

The primary purpose of Upper Garden Reservoir Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Greystone Park Psychiatric Hospital (state). It impounds the Whippany River-tr near Denvile.

The dam stands 6 feet tall and stretches 550 feet across, creates a reservoir covering 3 acres, and collects water from a drainage area of 0 square miles.

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 satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 06/28/2023.

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Significant HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateNew Jersey
CountyMorris
Nearest CityDenvile
River/StreamWhippany River-tr
Coordinates40.83813, -74.51540

Physical Characteristics

Dam TypeEarth
NID Height6 ft
Dam Height6 ft
Dam Length550 ft

Storage & Hydraulics

Surface Area3 acres
Drainage Area0 sq mi

Ownership & Safety

PurposeRecreation
OwnerGreystone Park Psychiatric Hospital
Owner TypeState
Hazard ClassificationSignificant
Condition AssessmentSatisfactory
Last Inspection06/28/2023
Emergency Action PlanYes

Identifiers

NID IDNJ01001
Federal IDNJ01001
More InfoState Dam Safety Program

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