Crystal Lake
Crystal Lake is a rockfill dam located in Petersburg Borough, Alaska, built in 1955. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Crystal Lake
The primary purpose of Crystal 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 Of Petersburg (local government). It impounds the Crystal Creek, Blind River near N/a.
The dam stands 43 feet tall and stretches 205 feet across, creates a reservoir covering 233 acres, has a maximum storage capacity of 5,800 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1955, 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 06/21/2022.
At 43 feet, this dam is taller than 89% of dams nationwide.
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 | Petersburg Borough |
| Nearest City | N/a |
| River/Stream | Crystal Creek, Blind River |
| Coordinates | 56.59969, -132.82924 |
Physical Characteristics
| Dam Type | Rockfill |
| NID Height | 43 ft |
| Dam Height | 43 ft |
| Dam Length | 205 ft |
| Year Completed | 1955 (71 years old) |
Storage & Hydraulics
| NID Storage | 5,800 acre-ft |
| Max Storage | 5,800 acre-ft |
| Normal Storage | 5,200 acre-ft |
| Surface Area | 233 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 2,632 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | City of Petersburg |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 06/21/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | AK00005 |
| Federal ID | AK00005 |
| More Info | State Dam Safety Program |