Cascade

Androscoggin River· Coos, New Hampshire· Built 1903· Concrete· 57 ft tall
High Hazard Hydroelectric Not Listed

Key Takeaway

Cascade is classified as high hazard in New Hampshire. It was completed in 1903 and is 123 years old. Its primary use is hydroelectric. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Height 57 ft (taller than 95.9% in NH)
Dam Length583 ft
Dam TypeConcrete
Max Storage200 acre-ft
Normal Storage200 acre-ft
Surface Area28 acres
Drainage Area1,361 sq mi
Max Discharge40,000 cfs
Year Completed1903 (123 years old)
NID IDNH00163

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

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

Emergency Action Plan: Yes
Last Inspection: July 13, 2022
State Regulated: Yes
Regulatory Agency: NHDES DAM BUREAU

Ownership

Not Listed

Nearby Dams

Cascade Wastewater Lagoon Dam

Coos, NH

Significant Hazard 13 ft

Cross Power

Coos, NH

High Hazard 25 ft

J. Brodie Smith

Coos, NH

High Hazard 31 ft

Riverside

Coos, NH

Low Hazard 21 ft

Sawmill

Coos, NH

Low Hazard 15 ft

Mt Carberry Leachate Pond Dam

Coos, NH

Significant Hazard 5 ft

Gorham

Coos, NH

Low Hazard 24 ft

Gorham

Coos, NH

Low Hazard 20 ft

Frequently Asked Questions

What is the hazard classification of Cascade?

Cascade is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Cascade?

Cascade is owned by information not available (Not Listed). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Cascade built?

Cascade was completed in 1903, making it 123 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 Cascade?

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

How tall is Cascade?

Cascade has a dam height of 57 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 Cascade last inspected?

Cascade was last inspected on July 13, 2022. 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.