Sly Park dam
Sly Park
Sly Park, also known as Jenkinson Lake, is a public utility water resource located in El Dorado County, California. This reservoir on Sly Park Creek serves multiple purposes, including irrigation, recreation, and water supply. The earth dam, completed in 1955, stands at 182 feet tall and has a storage capacity of 41,000 acre-feet. With a surface area of 677 acres and a drainage area of 17.2 square miles, Sly Park plays a crucial role in water management in the region.
Managed by the California Department of Water Resources (DWR) under the Safety of Dams program, Sly Park has a high hazard potential but is currently assessed as satisfactory in condition. Regular inspections are conducted to ensure the dam's safety and integrity. The reservoir's primary purpose is water supply, providing essential resources for the surrounding communities. Located in Nashville, California, Sly Park offers a scenic and recreational destination for visitors to enjoy water-based activities and picturesque views.
With a congressman representing the area as Tom McClintock (R), Sly Park is under state regulatory oversight, with permitting, inspection, and enforcement handled by the appropriate agencies. The dam's emergency action plan is regularly updated, and measures are in place to manage risks associated with its operation. Water resource and climate enthusiasts will find Sly Park to be an interesting case study in water management, dam safety, and the importance of sustainable water supply in California's diverse 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 Sly Park -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Pilot C Ab Stumpy Meadows Res Ca | 3 cfs | → |
| Pilot C Bl Mutton Canyon Nr Georgetown Ca | 2 cfs | → |
| Deer C Nr Cameron Park Ca | 8 cfs | → |
| Nf American R A North Fork Dam Ca | 732 cfs | → |
| Upper Truckee R At S Upper Truckee Rd Nr Meyers Ca | 4 cfs | → |
| Cosumnes R A Michigan Bar Ca | 329 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Sly Park.
Boat launches
- Sly Park Road, Pollock Pines
- Forebay Road El Dorado County
- Poho Ridge El Dorado County
- Junction Boat Ramp Road El Dorado County
- Rock Creek Road El Dorado County
- Dry Lakes Trail El Dorado County
Campgrounds
- Sly Park
- Pine Cone - Sly Park Recreation Area
- Hazel Creek - Sly Park Recreation Area
- Rainbow - Sly Park Recreation Area
- Deerwood - Sly Park Recreation Area
- Kane Xxx - Sly Park Recreation Area
Fishing spots
- Stumpy Meadows Lake
- Union Valley Reservoir
- Ice House Reservoir
- Wrights Lake
- Bear River Reservoir
- Lower Bear River Reservoir
Paddle runs
- Cosumnes Mine Road To Confluence With Steely Fork Cosumnes River
- Confluence With Van Horn Creek To Cosumnes Mine Road
- Confluence With Dogtown Creek To West Nf Boundary
- Two Miles West Of Pipi Campground To Confluence With Dogtown Creek
- One Mile East Of Pipi Campground To Two Miles West Of Pipi Campground
- South Fork American River
More reservoirs
Track Sly Park 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 Sly Park
Where does the data for Sly Park 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 Sly Park.