Lyman Number 1 Reservoir Report
Nearby: Lyman Number 3 Lyman Number 2
Last Updated: December 7, 2025
Lyman Number 1 is a private earth dam located in Jones, South Dakota, along the TR-BAD River.
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Summary
Built in 1962 by the Natural Resources Conservation Service, this dam stands at a height of 29 feet and has a length of 456 feet, providing a storage capacity of 58 acre-feet. Despite its age, the dam has a low hazard potential and is currently not rated in terms of condition assessment.
The dam is regulated by the South Dakota Department of Environment and Natural Resources, with state permitting, inspection, and enforcement processes in place. It is situated in the St. Paul District and falls under the jurisdiction of Congressman Dusty Johnson. Although there are no associated structures with Lyman Number 1, it serves a vital purpose in water resource management and flood control along the TR-BAD River.
Water resource and climate enthusiasts monitoring this area can appreciate the historical significance and engineering feats involved in the construction of Lyman Number 1. With its modest storage capacity and low hazard potential, this dam continues to play a crucial role in protecting the surrounding community from potential flooding events. The presence of regulatory oversight and compliance measures ensures the safety and integrity of this important infrastructure for years to come.
Year Completed |
1962 |
Dam Length |
456 |
Dam Height |
29 |
River Or Stream |
TR-BAD RIVER |
Primary Dam Type |
Earth |
Hydraulic Height |
29 |
Nid Storage |
58 |
Hazard Potential |
Low |
Nid Height |
29 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Dam Data Reference
Condition Assessment
SatisfactoryNo 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
HighDams 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.
Lyman Number 1