Lower Lake Royer Reservoir Report

Last Updated: December 5, 2025

Lower Lake Royer, also known as Fort Ritchie Dam, is a captivating water resource nestled in the Washington County of Maryland.


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Summary

Constructed in 1898 by the US Army Corps of Engineers, this earth-type dam stands at a height of 19 feet and spans 900 feet in length, with a storage capacity of 230 acre-feet. The dam primarily serves as a water supply source, with additional purposes for recreation, making it a vital resource for both human consumption and leisure activities.

The dam's spillway, an uncontrolled type with a width of 45 feet, can handle a maximum discharge of 800 cubic feet per second. Despite being rated as having a high hazard potential, Lower Lake Royer is deemed to be in fair condition as of the last assessment in February 2021. Regular inspections and enforcement by Maryland Dam Safety ensure the safety and integrity of the structure, with a moderate risk level assigned.

With its scenic location and historical significance, Lower Lake Royer offers a unique blend of water supply functionality and recreational opportunities. Climate and water resource enthusiasts can appreciate the engineering marvel of this dam, its impact on the local ecosystem, and the efforts in place to manage risks and ensure public safety.

Years Modified

1995 - Structural

Year Completed

1898

Dam Length

900

Dam Height

19

River Or Stream

Falls Creek-TR

Primary Dam Type

Earth

Surface Area

10.7

Drainage Area

1.9

Nid Storage

230

Outlet Gates

Slide (sluice gate) - 0

Hazard Potential

High

Foundations

Rock

Nid Height

19
       
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.