Blue Marsh Lake Reservoir Report

Last Updated: December 6, 2025

Blue Marsh Lake, located in Berks County, Pennsylvania, was constructed in the early 1970s for flood control, water supply, and recreational purposes.


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Summary

The lake is part of the Tulpehocken Creek Watershed and is fed by the Tulpehocken Creek and several smaller tributaries. The hydrology of the lake is managed by the U.S. Army Corps of Engineers and includes a system of dams, reservoirs, and pumping stations to maintain water levels.

Surface flow providers include the Tulpehocken Creek, Spring Creek, Dry Brooks, and Blue Marsh Creek, while snowpack can contribute to water levels during the winter months. The lake provides water for local agriculture and is also used for recreational activities such as boating, fishing, biking, and hiking. The area surrounding the lake is managed by the U.S. Army Corps of Engineers and offers various amenities such as campgrounds, picnic areas, and a beach.

Reservoir Details

Elevation Of Reservoir Water Surface Above Datum, Ft 24hr Change 0.0%
Percent of Normal 100%
Minimum 281.89 ft
2010-09-28
Maximum 319.63 ft
2022-01-21
Average 285 ft
Hydraulic_Height 94
Drainage_Area 175
Year_Completed 1977
Nid_Storage 129900
Structural_Height 100
Primary_Dam_Type Rockfill
Surface_Area 1147
Hazard_Potential High
Outlet_Gates Slide (sluice gate) - 0
River_Or_Stream TULPEHOCKEN CREEK
Dam_Length 1775
Nid_Height 100
       
Seasonal Comparison
Precipitation, Total, In Levels
Elevation Of Reservoir Water Surface Above Datum, Ft Levels

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.