Lock

Allagash Stream· Piscataquis, Maine· Built 1875· Timber Crib· 15 ft tall
Low Hazard Hydroelectric Flood Risk Reduction State Government

Key Takeaway

Lock is classified as low hazard in Maine. It was completed in 1875 and is 151 years old. Its primary use is hydroelectric.

Physical Details

Dam Height 15 ft (taller than 51.7% in ME)
Dam Length280 ft
Dam TypeTimber Crib
Max Storage105.2K acre-ft
Normal Storage101.0K acre-ft
Surface Area11,200 acres
Drainage Area204 sq mi
Year Completed1875 (151 years old)
NID IDME00198

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: No
Last Inspection: November 7, 2007
State Regulated: Yes
Regulatory Agency: MEMA

Ownership

BPL, DOC/State of Maine (Allagash Wilderness Waterway)

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lock?

Lock is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Lock?

Lock is owned by BPL, DOC/State of Maine (Allagash Wilderness Waterway) (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lock built?

Lock was completed in 1875, making it 151 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.

What is the primary purpose of Lock?

Lock serves the following purposes: Hydroelectric, Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Lock?

Lock has a dam height of 15 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.

When was Lock last inspected?

Lock was last inspected on November 7, 2007. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.