Twin Lakes Reservoir Report

Last Updated: December 13, 2025

Twin Lakes, located in Elk County, Pennsylvania, is a picturesque federal recreation area that offers opportunities for fishing and wildlife observation.


°F

°F

mph

Wind

%

Humidity

Summary

The earth dam, completed in 1936 by the USDA Forest Service, stands at a height of 18 feet and spans 380 feet in length. The reservoir has a storage capacity of 117 acre-feet, with a normal storage level of 44 acre-feet and a surface area of 7 acres.

Despite being a significant hazard potential dam with a moderate risk assessment rating, Twin Lakes has not been recently assessed for its condition. The spillway, which is uncontrolled and 30 feet wide, can handle a maximum discharge of 3600 cubic feet per second. The dam's primary purpose is for recreation, with Hoffman Run serving as the primary river or stream that feeds into the reservoir.

Water resource and climate enthusiasts will appreciate the natural beauty and recreational opportunities offered by Twin Lakes, while also being intrigued by the dam's historical significance and potential risks associated with its condition. As a federal recreation area managed by the Forest Service, Twin Lakes provides a serene escape for visitors to enjoy the tranquility of nature while also being mindful of the dam's structural integrity and safety measures in place.

Year Completed

1936

Dam Length

380

Dam Height

18

River Or Stream

HOFFMAN RUN

Primary Dam Type

Earth

Surface Area

7

Hydraulic Height

18

Drainage Area

5

Nid Storage

117

Structural Height

29

Hazard Potential

Significant

Nid Height

29
       
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.