Onstead Gss Reservoir Report

Last Updated: December 6, 2025

Onstead Gss is a private earth dam located in Waller, Texas, along the TR-Cedar Creek river.


°F

°F

mph

Wind

%

Humidity

Summary

Constructed in 1974 by the USDA NRCS, this dam stands at a height of 21 feet and has a storage capacity of 127 acre-feet. Despite its age, the dam's condition assessment is currently marked as "Not Rated", raising concerns about its structural integrity and potential hazard.

With a high risk assessment score of 2, Onstead Gss poses a significant risk to the surrounding area in the event of a breach or failure. The dam lacks a spillway and has not been inspected or assessed for condition recently, further highlighting the need for proactive risk management measures. The presence of only one outlet gate adds to the potential challenges in managing water levels and downstream flows in case of emergencies.

As water resources and climate enthusiasts, it is crucial to monitor and advocate for proper maintenance and assessment of dams like Onstead Gss to ensure the safety of communities and the environment. With its high hazard potential and outdated condition assessment, urgent action is needed to mitigate risks and protect downstream areas from potential flooding or catastrophic events.

Year Completed

1974

Dam Length

832

Dam Height

21

River Or Stream

TR-CEDAR CREEK

Primary Dam Type

Earth

Hydraulic Height

21

Nid Storage

127

Structural Height

21

Outlet Gates

None - 1

Hazard Potential

Not Available

Foundations

Unlisted/Unknown

Nid Height

21
       
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.