Prince William Parkway Regional Swm

Prince William Parkway Regional Swm is an earth dam located in Prince William County, Virginia. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Prince William Parkway Regional Swm

The primary purpose of Prince William Parkway Regional Swm is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Prince William County (local government). It impounds the Cow Branch.

The dam stands 48 feet tall and stretches 470 feet across, creates a reservoir covering 3 acres, has a maximum storage capacity of 316 acre-feet, and collects water from a drainage area of 0 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 03/16/2022.

At 48 feet, this dam is taller than 92% 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.

High HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateVirginia
CountyPrince William
River/StreamCow Branch
Coordinates38.65100, -77.29280

Physical Characteristics

Dam TypeEarth
NID Height48 ft
Dam Height48 ft
Dam Length470 ft

Storage & Hydraulics

NID Storage316 acre-ft
Max Storage316 acre-ft
Normal Storage25 acre-ft
Surface Area3 acres
Drainage Area0 sq mi

Ownership & Safety

PurposeFlood Risk Reduction
OwnerPrince William County
Owner TypeLocal Government
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection03/16/2022
Emergency Action PlanYes

Identifiers

NID IDVA153022
Federal IDVA153022
More InfoState Dam Safety Program

Nearby Dams