Franklin Falls Dam

Franklin Falls Dam is a rockfill dam located in Merrimack County, New Hampshire, built in 1943. It carries a High hazard potential classification.

About Franklin Falls Dam

The primary purpose of Franklin Falls Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Usace - New England District (federal). It impounds the Pemigewasset River near Franklin.

The dam stands 116 feet tall and stretches 1,740 feet across, creates a reservoir covering 440 acres, has a maximum storage capacity of 222,000 acre-feet, and collects water from a drainage area of 1,000 square miles. Completed in 1943, the structure is well-established, with more than 75 years of service.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. An emergency action plan is in place for this dam. The most recent inspection on record was 06/18/2024.

At 116 feet, this dam is taller than 98% of all dams in the United States.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The New Hampshire dam safety program can provide more specific information about emergency planning for this structure.

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

High HazardNot Available ConditionEmergency Action Plan: Yes

Location

StateNew Hampshire
CountyMerrimack
Nearest CityFranklin
River/StreamPemigewasset River
Coordinates43.46895, -71.65931

Physical Characteristics

Dam TypeRockfill
NID Height116 ft
Dam Height116 ft
Dam Length1,740 ft
Year Completed1943 (83 years old)

Storage & Hydraulics

NID Storage222,000 acre-ft
Max Storage222,000 acre-ft
Normal Storage3,000 acre-ft
Surface Area440 acres
Drainage Area1,000 sq mi
Max Discharge205,000 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeFlood Risk Reduction
OwnerUSACE - New England District
Owner TypeFederal
Hazard ClassificationHigh
Condition AssessmentNot Available
Last Inspection06/18/2024
Emergency Action PlanYes

Identifiers

NID IDNH00003
Federal IDNH00003
More InfoState Dam Safety Program

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