Winslow Dam Reservoir Report

Last Updated: December 5, 2025

Winslow Dam, also known as Seneca Lake, is a private-owned structure located in Fauquier, Virginia, along the Negro Run stream.


°F

°F

mph

Wind

%

Humidity

Summary

Its primary purpose is for recreation, offering a serene and picturesque setting for water and outdoor enthusiasts. The dam stands at 35.5 feet high, with a storage capacity of 779 acre-feet and a drainage area of 1.72 square miles.

Despite its scenic beauty, Winslow Dam has been assessed as having a significant hazard potential and poor condition as of March 2021. The dam's inspection frequency is set at once per year, with the last assessment conducted on March 23, 2021. The state of Virginia regulates and inspects the dam, ensuring that it meets safety standards for its recreational use. While the dam's emergency action plan status and risk assessment remain unclear, its location in a tranquil setting makes it a popular destination for outdoor activities.

Winslow Dam offers a tranquil escape for water resource and climate enthusiasts, providing a recreational oasis in the heart of Virginia. With its significant hazard potential and poor condition, the dam is closely monitored and regulated by the Department of Conservation and Recreation. Despite these challenges, the dam continues to be a popular destination for outdoor activities, attracting visitors with its serene surroundings and opportunities for relaxation and enjoyment.

Dam Length

510

Dam Height

35.5

River Or Stream

Negro Run

Primary Dam Type

Earth

Drainage Area

1.72

Nid Storage

779

Hazard Potential

Significant

Nid Height

36
       
Seasonal Comparison

Weather Forecast

Dam Data Reference

Condition Assessment

Satisfactory
No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.

Hazard Potential Classification

High
Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.