Speedwell Forge Reservoir Report

Last Updated: December 8, 2025

Speedwell Forge is a state-owned recreational water resource located in Lancaster, Pennsylvania, along Hammer Creek.


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Summary

The dam, completed in 1966, stands at a height of 35 feet and spans 950 feet, with a storage capacity of 2,372 acre-feet and a normal storage of 970 acre-feet. The dam serves primarily for recreation purposes and is regulated by the Pennsylvania Department of Environmental Protection.

Despite its satisfactory condition assessment, Speedwell Forge poses a high hazard potential, necessitating regular inspections and enforcement by state authorities. The dam's location in Elizabeth Township adds to its importance as a water resource and recreational area in the region. With a surface area of 106 acres and a drainage area of 24.1 square miles, the dam plays a crucial role in managing water flow and storage in the area.

Water resource and climate enthusiasts interested in Speedwell Forge will find a captivating mix of environmental factors, recreational opportunities, and regulatory oversight at this state-owned earth dam. Its historical significance, high hazard potential, and state-regulated status make it a compelling site for exploration and study in the world of water resource management and climate resilience.

Year Completed

1966

Dam Length

950

Dam Height

35

River Or Stream

HAMMER CREEK

Primary Dam Type

Earth

Surface Area

106

Drainage Area

24.1

Nid Storage

2372

Hazard Potential

High

Foundations

Unlisted/Unknown

Nid Height

35
       
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.