Law Reservoir Report

Last Updated: December 5, 2025

Law, John is a historic earth dam located in Windsor, Colorado, completed in 1896 for irrigation purposes along the Slough river.


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Summary

With a height of 14 feet and a length of 500 feet, this dam has a storage capacity of 310 acre-feet and serves as a vital water resource for the surrounding area. Despite its age, Law, John is still in operation, regulated by the Colorado Department of Water Resources, and undergoes regular inspections to ensure its structural integrity.

The dam's spillway, with a width of 160 feet, is uncontrolled, and the hazard potential is rated as low. However, the condition assessment in June 2020 revealed that Law, John was in an unsatisfactory state, warranting further attention and maintenance. It is noteworthy that the risk assessment for this dam is moderate (3), indicating a need for proactive risk management measures to mitigate potential hazards and ensure the safety of the downstream community in case of emergencies.

Law, John's rich history, combined with its essential role in providing irrigation water to the region, makes it a significant landmark for water resource and climate enthusiasts. As efforts are made to address its current unsatisfactory condition and manage potential risks, this dam continues to stand as a testament to the importance of maintaining and safeguarding our water infrastructure for future generations.

Year Completed

1896

Dam Length

500

Dam Height

14

River Or Stream

SLOUGH

Primary Dam Type

Earth

Surface Area

15

Hydraulic Height

14

Drainage Area

36

Nid Storage

310

Structural Height

14

Hazard Potential

Low

Nid Height

14
       
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.