Longeway Dam Reservoir Report
Last Updated: December 13, 2025
Longeway Dam, also known as Deer Lake Dam, is a privately owned structure located in Ferry County, Washington.
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Summary
Completed in 1970, this Earth-type dam serves primarily for recreational purposes, providing a surface area of 14 acres and a maximum storage capacity of 80 acre-feet. Situated on an unnamed tributary of the Sanpoil River, Longeway Dam has a hydraulic height of 11 feet and a structural height of 11 feet, with a drainage area of 0.71 square miles.
Managed by the Washington Department of Ecology, Longeway Dam has a low hazard potential and is currently rated as "Not Rated" in terms of condition assessment. While the dam does not have an Emergency Action Plan in place or updated inundation maps, it is subject to state regulation, inspection, and enforcement to ensure its safety and compliance with standards. With a maximum discharge capacity of 100 cubic feet per second, Longeway Dam remains a vital part of the local water resource infrastructure in the region.
Despite its modest size and recreational focus, Longeway Dam plays a crucial role in water management and conservation efforts in Ferry County, Washington. As climate change continues to impact water resources and ecosystems, structures like Longeway Dam are essential for maintaining a balance between human needs and environmental sustainability. By staying vigilant and proactive in its maintenance and regulation, Longeway Dam stands as a testament to responsible water resource management in the face of changing conditions.
Year Completed |
1970 |
Dam Length |
110 |
River Or Stream |
Unnamed Trib - Sanpoil R. |
Primary Dam Type |
Earth |
Surface Area |
14 |
Hydraulic Height |
11 |
Drainage Area |
0.71 |
Nid Storage |
80 |
Structural Height |
11 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
11 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Kettle River Near Ferry
|
353cfs |
Colville River At Kettle Falls
|
182cfs |
Kettle River Near Laurier
|
806cfs |
Okanogan River Near Tonasket
|
9730cfs |
Okanogan River At Oroville
|
352cfs |
Omak Creek Near Omak
|
7cfs |
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.
Area Campgrounds
| Location | Reservations | Toilets |
|---|---|---|
Curlew Lake State Park
|
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Lambert Horse Camp
|
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Old Stage Horse Camp
|
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Jungle Hill Horse Campground
|
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Ten Mile
|
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Ten Mile Campground
|
Longeway Dam