J Deckert #1 Reservoir Report
Nearby: Wold Ding-A-Ling
Last Updated: December 7, 2025
J Deckert #1 is a state-owned dam located in Poplar, Montana, on the South Fork Lisk Creek.
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Summary
Built in 1960, this earth dam stands at a height of 20 feet and serves multiple purposes, including fire protection, stock watering, and as a small fish pond, with a total storage capacity of 82 acre-feet. The dam is regulated by the Montana Department of Natural Resources and Conservation (DNRC), with state permitting, inspection, and enforcement in place to ensure its safety and compliance with regulations.
Despite its low hazard potential, J Deckert #1 has not been condition-rated and lacks an emergency action plan (EAP) as of the last data update in April 2022. The dam is designed to withstand hydraulic pressures up to 20 feet and has a length of 200 feet. While the dam is not under the jurisdiction of the US Army Corps of Engineers, it plays a crucial role in providing essential water resources for fire protection and agricultural activities in the region. Water resource and climate enthusiasts will find J Deckert #1 to be an interesting case study in the management and regulation of small dams for multiple purposes.
Year Completed |
1960 |
Dam Length |
200 |
Dam Height |
20 |
River Or Stream |
SOUTH FORK LISK CREEK |
Primary Dam Type |
Earth |
Hydraulic Height |
20 |
Nid Storage |
82 |
Hazard Potential |
Low |
Nid Height |
20 |
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.
J Deckert #1