Long Lake Dam

LONG RIVER· City and Borough of Juneau, Alaska· Built 1973· Concrete·
Low Hazard Hydroelectric Public Utility

Key Takeaway

Long Lake Dam is classified as low hazard in Alaska. It was completed in 1973 and is 53 years old. Its primary use is hydroelectric.

Physical Details

Dam Length337 ft
Dam TypeConcrete
Max Storage147.0K acre-ft
Normal Storage147.0K acre-ft
Surface Area1,375 acres
Drainage Area32 sq mi
Max Discharge28,000 cfs
Year Completed1973 (53 years old)
NID IDAK00044

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: August 28, 2019
State Regulated: Yes
Regulatory Agency: AKDNR

Ownership

ALASKA INDUSTRIAL DEVELOPMENT AND EXPORT AUTHORITY

Public Utility

Frequently Asked Questions

What is the hazard classification of Long Lake Dam?

Long Lake Dam 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 Long Lake Dam?

Long Lake Dam is owned by ALASKA INDUSTRIAL DEVELOPMENT AND EXPORT AUTHORITY (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Long Lake Dam built?

Long Lake Dam was completed in 1973, making it 53 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 Long Lake Dam?

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

When was Long Lake Dam last inspected?

Long Lake Dam was last inspected on August 28, 2019. 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.