Twin Lake dam
Twin Lake
Twin Lake, located in Alpine County, California, is a privately owned reservoir with a primary purpose of hydroelectric power generation. Built in 1903, this earth dam stands at 22 feet high and spans 1520 feet in length. With a storage capacity of 21,581 acre-feet, it serves as a crucial water resource for the surrounding area, particularly during dry seasons. The dam is regulated by both state and federal agencies, ensuring its safety and compliance with inspection and enforcement protocols.
The North Fork Mokelumne River-tr flows through Twin Lake, providing a source of water for the reservoir. The dam's spillway, with a width of 296 feet, is uncontrolled and can handle a maximum discharge of 12,400 cubic feet per second. Despite its low hazard potential, Twin Lake is subject to moderate risk assessment due to its age and condition assessment being unavailable. Emergency action plans have been prepared and revised periodically, with maintenance measures in place to mitigate any potential risks associated with the dam's operation.
The picturesque setting of Twin Lake, nestled in the scenic Kirkwood area, offers not only a source of hydroelectric power but also a recreational spot for visitors to enjoy. With its historical significance dating back over a century, Twin Lake stands as a testament to the intersection of water resource management, climate resilience, and sustainable energy generation in the California landscape.
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 Twin Lake -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| E F Carson R Bl Markleeville C Nr Markleevilleca | 978 cfs | → |
| West Fork Carson River At Woodfords | 237 cfs | → |
| Upper Truckee R At S Upper Truckee Rd Nr Meyers Ca | 4 cfs | → |
| Leviathan C Channel Underdrain Nr Markleeville Ca | 0 cfs | → |
| Leviathan Mine Adit Drain Nr Markleeville Ca | 0 cfs | → |
| 4l C Nr Markleeville Ca | 0 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Twin Lake .
Boat launches
- Amador County
- Summit Lake Trail Alpine County
- Indian Creek Camp Ground Day Use Area
- Topaz Park Road Douglas County
- Cave Rock Boat Launch Douglas County
Campgrounds
- Lower Blue Lake Campgroung (Pg&E)
- Lower Blue Lake
- Middle Creek/Expansion
- Upper Blue Lake Dam
- Upper Blue Lake
- Lost Campings
Fishing spots
Paddle runs
- Headwaters In Sec 2, T9n, R18e To Confluence With Mokelumne River
- Highway 4 To Salt Springs Reservoir
- Headwaters In Sec 15,T10n, R17e To Confluence With Silver Fork Of American River
- Centerville Flat To Hangman's Bridge
- Source Sec 24, T6n, R21e To Centerville Flat
- Headwaters To South Of Upper Truckee Road (Sec Line Between 17/20 Intercepts River And Unnamed Tributary)
Track Twin 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 Twin Lake
Where does the data for Twin 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 Low 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 Twin Lake .