Lake Fairfax Dam
Lake Fairfax Dam is an earth dam located in Fairfax County, Virginia. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Lake Fairfax Dam
The primary purpose of Lake Fairfax Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Fairfax County Park Authority (local government). It impounds the Colvin Run.
The dam stands 32 feet tall and stretches 500 feet across, creates a reservoir covering 21 acres, has a maximum storage capacity of 487 acre-feet, and collects water from a drainage area of 4 square miles.
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 08/19/2022.
At 32 feet, this dam is taller than 76% 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 Virginia 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 | Virginia |
| County | Fairfax |
| River/Stream | Colvin Run |
| Coordinates | 38.96460, -77.31740 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 32 ft |
| Dam Height | 32 ft |
| Dam Length | 500 ft |
Storage & Hydraulics
| NID Storage | 487 acre-ft |
| Max Storage | 487 acre-ft |
| Normal Storage | 182 acre-ft |
| Surface Area | 21 acres |
| Drainage Area | 4 sq mi |
Ownership & Safety
| Purpose | Recreation |
| Owner | Fairfax County Park Authority |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 08/19/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | VA059010 |
| Federal ID | VA059010 |
| More Info | State Dam Safety Program |