Occoquan Lower Storage Dam dam
Occoquan Lower Storage Dam
The Occoquan Lower Storage Dam, located in Fairfax, Virginia, serves as a vital water supply resource for the region, with a storage capacity of 170 acre-feet. This gravity dam, standing at 20 feet in height and stretching 484 feet in length, plays a crucial role in regulating the flow of the Occoquan River. The dam's primary purpose is for water supply, but it also has capabilities for hydroelectric power generation.
Managed by the Department of Conservation and Recreation in Virginia, the Occoquan Lower Storage Dam undergoes regular inspections to ensure its structural integrity and safety. With a high hazard potential due to its location and function, the dam is rated as satisfactory in terms of its condition assessment. The last inspection in November 2020 confirmed its operational readiness and highlighted its importance in maintaining a reliable water source for the surrounding communities. For water resource and climate enthusiasts, the Occoquan Lower Storage Dam stands as a symbol of sustainable water management and conservation efforts in the region.
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 Occoquan Lower Storage Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Long Branch Near Annandale | 1 cfs | → |
| Accotink Creek Near Annandale | 3 cfs | → |
| S F Quantico Creek Near Independent Hill | 0 cfs | → |
| Cameron Run At Alexandria | 6 cfs | → |
| Mattawoman Creek Near Pomonkey | 1 cfs | → |
| Fourmile Run At Alexandria | 3 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Occoquan Lower Storage Dam.
Boat launches
- Forest Hill Road Lake Ridge
- Marshall Hall Boat Ramp Charles County
- Ludgate Drive Mount Vernon
- Doves Trail Prince William County
- Sinclair Lane Prince William County
- Wharf Road Accokeek
Campgrounds
- Burke Lake Park
- Pohick Bay Regional Park
- Fort Belvoir Travel And Rv Camp
- Prince William Forest Rv Campground
- Cabin Camp 1
- Cabin Camp 4 - Pleasant Historic District
Fishing spots
Track Occoquan Lower Storage Dam 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 Occoquan Lower Storage Dam
Where does the data for Occoquan Lower Storage Dam 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 Occoquan Lower Storage Dam.