Blue Lake
Blue Lake is an arch dam located in City and Borough of Sitka, Alaska, built in 1961. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Blue Lake
The primary purpose of Blue Lake is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by City And Borough Of Sitka (local government). It impounds the Sawmill Creek.
The dam stands 294 feet tall and stretches 288 feet across, creates a reservoir covering 1,646 acres, has a maximum storage capacity of 266,000 acre-feet, and collects water from a drainage area of 37 square miles. Completed in 1961, the structure is well into its service life at over 50 years old.
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. 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 08/01/2022.
At 294 feet, this dam is taller than 99% 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 Alaska 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.
Location
| State | Alaska |
| County | City and Borough of Sitka |
| Nearest City | None |
| River/Stream | Sawmill Creek |
| Coordinates | 57.06286, -135.19850 |
Physical Characteristics
| Dam Type | Arch |
| NID Height | 294 ft |
| Dam Height | 294 ft |
| Dam Length | 288 ft |
| Year Completed | 1961 (65 years old) |
Storage & Hydraulics
| NID Storage | 266,000 acre-ft |
| Max Storage | 266,000 acre-ft |
| Normal Storage | 266,000 acre-ft |
| Surface Area | 1,646 acres |
| Drainage Area | 37 sq mi |
| Max Discharge | 14,000 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | City and Borough of Sitka |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 08/01/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | AK00002 |
| Federal ID | AK00002 |
| More Info | State Dam Safety Program |