Lyle Reservoir Reservoir Report
Last Updated: December 6, 2025
Lyle Reservoir, located in Maupin, Oregon, along Wilson Creek, is a privately owned irrigation reservoir completed in 1911.
°F
°F
mph
Wind
%
Humidity
Summary
With a dam height of 12 feet and a capacity of 103 acre-feet, the reservoir serves as a vital water source for agricultural purposes in the region. The reservoir covers an area of 10.8 acres and has a maximum discharge of 140 cubic feet per second.
Managed by the Oregon Water Resources Department, Lyle Reservoir is regulated and inspected to ensure its safety and compliance with state regulations. With a low hazard potential and a condition assessment of "Not Rated," the reservoir has a history of reliable operation. While the last inspection date was in 1990, the reservoir is subject to regular inspections every 6 years to assess its structural integrity and functionality.
Despite its age, Lyle Reservoir continues to play a crucial role in sustaining the local agricultural community by providing irrigation water. With its gravity dam design and historical significance dating back over a century, the reservoir stands as a testament to the importance of water resource management in the face of changing climate conditions.
Year Completed |
1911 |
Dam Length |
740 |
Dam Height |
12 |
River Or Stream |
WILSON CREEK |
Primary Dam Type |
Gravity |
Surface Area |
10.8 |
Hydraulic Height |
12 |
Drainage Area |
49.5 |
Nid Storage |
103 |
Structural Height |
15 |
Hazard Potential |
Low |
Nid Height |
15 |
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.
Trout Creek - Madras
D88.77R
D88.79R
D88.94R
D89.00R
D90.07R
Lyle Reservoir