Lake Mary dam
Lake Mary
Lake Mary, located in Soda Springs, California, is a privately owned dam designed for flood risk reduction along the Tr Sfk Yuba River. Built in 1926, this earth-type dam stands at 22 feet high and stretches for 600 feet, providing a storage capacity of 172 acre-feet. With a low hazard potential and a satisfactory condition assessment, Lake Mary has been regulated, permitted, inspected, and enforced by the California Department of Water Resources, Safety of Dams division, ensuring its safety and structural integrity.
This tranquil reservoir covers an area of 18 acres and serves multiple purposes, including flood risk reduction, irrigation, and water supply. Despite its modest drainage area of 0.26 square miles, Lake Mary plays a vital role in managing water resources and mitigating potential risks in the region. The dam's last inspection in August 2020 revealed no major concerns, further reinforcing its important role in the community's water management infrastructure.
Managed by private owners, Lake Mary remains a key feature in the landscape of Placer County, California, under the jurisdiction of state regulatory agencies. With its historical significance dating back nearly a century, this dam continues to stand as a testament to responsible water resource management and climate resilience in the face of evolving environmental challenges.
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 Lake Mary -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Donner C A Donner Lk Nr Truckee Ca | 10 cfs | → |
| Donner C At Hwy 89 Nr Truckee Ca | 88 cfs | → |
| Truckee R Nr Truckee Ca | 519 cfs | → |
| Sagehen C Nr Truckee Ca | 13 cfs | → |
| Independence C Nr Truckee Ca | 10 cfs | → |
| Prosser C Bl Prosser C Dam Nr Truckee Ca | 71 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Lake Mary.
Boat launches
- Prosser Lake Reservoir
- Mosquito Ridge Rd, California
- Capt Roberts Boating Site
- Lake Spaulding Road 10260, Nevada City
- Meadow Lake Road Nevada County
- Woodcamp Access Road Nevada County
Campgrounds
- Muninnvagl
- Donner Memorial State Park
- First Campsite On The Left (3-4 Tents)
- Iron Throne Campsite (2 Tents)
- Hillside Campsite (2-3 Tents)
- Lakeside Balcony Campsite (1 Tent)
Fishing spots
Paddle runs
- Royal Gorge (Soda Springs To Tadpole Creek)
- Headwaters Se 1/4 Of Sec 10, T18, R15e To Stampede Reservoir
- Tahoe City To River Ranch
- Generation And Giant Gaps (Tadpole To Colfax-Iowa Hill Road)
- Hell Hole Dam To Ellicotts Bridge
- Langs Crossing Bridge To One-Half Mile West Of Confluence With Fall Creek (Boundary Of Nf And Private Land)
Track Lake Mary 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 Lake Mary
Where does the data for Lake Mary 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 Lake Mary.