Monhagen Lake Dike Reservoir Report

Last Updated: December 7, 2025

Monhagen Lake Dike, also known as Reservoir #1 Dike, is a crucial water supply infrastructure owned by the local government in Middletown, New York.


°F

°F

mph

Wind

%

Humidity

Summary

Constructed in 1867, this earth dam stands at a height of 20 feet and has a storage capacity of 858 acre-feet, with a normal storage level of 635 acre-feet. The dam is situated on the Monhagen Brook, serving as a vital source of water for the surrounding area.

Despite its historical significance, Monhagen Lake Dike poses a high hazard potential due to its condition assessment being marked as fair. The dam has been inspected periodically, with the last assessment conducted in February 2017 and a hazard rating of 2. While there have been no recent modifications or associated structures reported, the dam's emergency action plan status and risk management measures remain unclear. With a maximum discharge capacity of 799 cubic feet per second, it is essential for stakeholders and authorities to ensure the safety and maintenance of this critical water resource infrastructure.

Given its importance in water supply management and the potential risks associated with its condition, monitoring and regular inspections of Monhagen Lake Dike are imperative to mitigate any potential hazards. With its location in a high-risk area and the absence of certain emergency preparedness measures, continued attention and investment in the upkeep and safety of the dam are essential to safeguard the community and environment surrounding Monhagen Lake.

Year Completed

1867

Dam Height

20

River Or Stream

MONHAGEN BROOK

Primary Dam Type

Earth

Surface Area

65

Drainage Area

0.6

Nid Storage

858

Hazard Potential

High

Nid Height

20
       
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.