Agnew Lake dam
Agnew Lake
Agnew Lake, located in Mono County, California, is a private hydroelectric facility with a primary purpose of generating power. This concrete dam, completed in 1916, stands at a height of 30 feet and has a storage capacity of 810 acre-feet. The dam spans 278 feet in length and is situated on Rush Creek, with a drainage area of 23 square miles.
The dam at Agnew Lake has a high hazard potential and is regulated by both state and federal agencies, including the California Department of Water Resources and the Federal Energy Regulatory Commission. While the condition assessment is not available, regular inspections are conducted to ensure its safety and compliance with regulations. The dam also serves for recreational purposes, offering a surface area of 40 acres for outdoor activities.
With its historical significance and crucial role in energy production and water management, Agnew Lake is a notable structure in the region. Its location near June Lake and its architectural features make it a point of interest for water resource and climate enthusiasts looking to explore the intersection of human ingenuity and natural landscapes.
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.
- 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.
- 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.
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, environmental 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.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Agnew Lake -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Mf San Joaquin R Nr Mammoth Lakes Ca | 595 cfs | → |
| Deadman C A Big Springs Nr Crestview Ca | 37 cfs | → |
| Hot C A Flume Nr Mammoth Lakes Ca | 65 cfs | → |
| Merced R A Happy Isles Bridge Nr Yosemite Ca | 1,730 cfs | → |
| Green Creek Near Bridgeport | 60 cfs | → |
| Merced R A Pohono Bridge Nr Yosemite Ca | 2,040 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Agnew Lake .
⚓ Boat launches
- Gull Meadows Car Top Boat Launch
- Navy Beach Paddle Boat Launch
- Lake Edison Boating Site
- Mammoth Pool Rd, California
⛺ Campgrounds
- Silver Lake - June Lake
- Reversed Creek Campground
- Reversed Creek
- Gull Lake Campground
- Gull Lake
- Aerie Crag Picnic Area
🎣 Fishing spots
More fishing →🛶 Paddle runs
- Headwaters At Thousand Island Lake To Agnew Meadows
- Headwaters To Wilderness Boundary
- Confluence With Glass Creek To Big Springs
- Headwaters To Walker Lake
- National Monument Boundary To Soda Springs Footbridge In Devils Postpile National Monument
- Agnew Meadows To Soda Springs Footbridge
🛡 More reservoirs
More reservoirs →Track Agnew Lake in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Agnew Lake
Where does the data for Agnew Lake come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the High hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Agnew Lake .