Upper Occoquan Sewage Authority Dam dam
Upper Occoquan Sewage Authority Dam
The Upper Occoquan Sewage Authority Dam, located in Fairfax, Virginia, is a vital structure regulated by the Department of Conservation and Recreation. Standing at a height of 41 feet and with a length of 1680 feet, this earth dam serves the primary purpose of managing water resources in the area, specifically along the TR-Bull Run river. With a normal storage capacity of 515 acre-feet and a maximum storage of 1130 acre-feet, the dam plays a crucial role in flood control and water supply management for the surrounding communities.
Despite its satisfactory condition assessment as of September 2020, the Upper Occoquan Sewage Authority Dam has a high hazard potential, necessitating regular inspections and maintenance to ensure its continued safe operation. The dam's emergency action plan, last revised in November 2019, is a crucial component in mitigating risks and ensuring public safety in the event of a potential breach or overflow. With local government ownership and state regulation, this dam exemplifies the collaborative efforts required to manage and protect water resources in the face of climate change and increasing water-related challenges.
As climate change continues to impact water resources and infrastructure, the Upper Occoquan Sewage Authority Dam stands as a critical asset in Fairfax, Virginia's water management system. By meeting regulatory standards, conducting regular inspections, and maintaining a robust emergency action plan, this dam plays a pivotal role in safeguarding the community against potential hazards and ensuring the sustainable use of water resources for future generations. Its location along the TR-Bull Run river underscores its importance in flood control, water supply management, and overall resilience in the face of evolving environmental pressures.
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 Upper Occoquan Sewage Authority Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Long Branch Near Annandale | 52 cfs | → |
| Accotink Creek Near Annandale | 411 cfs | → |
| Cedar Run Near Catlett | 5 cfs | → |
| S F Quantico Creek Near Independent Hill | 0 cfs | → |
| Goose Creek Near Leesburg | 67 cfs | → |
| Difficult Run Near Great Falls | 149 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Upper Occoquan Sewage Authority Dam.
Boat launches
- Sinclair Lane Prince William County
- Doves Trail Prince William County
- Forest Hill Road Lake Ridge
- Ashburn Village Boulevard 20585, Lansdowne
- Potomac Hills Street Fairfax County
- Rogues Road Fauquier County
Campgrounds
Fishing spots
- Gillam Branch (Historical)
- Davis Branch (Historical)
- Maddox Branch
- Washington Aqueduct
- Dalecarlia Reservoir
- Georgetown Reservoir
Paddle runs
- Bixler Bridge On State Route 675 To Karo Landing, Approximately 6 Miles South Of Town Of Front Royal
- Segment C--Nf Boundary To Confluence With North Fork Shenandoah River
- Segment B--State Route 730 Bridge To Nf Boundary
- State Route 675 At Edinburg, Va To State Highway 55 Southeast Of Strasburg, Va
- Headwaters Adjacent To Fdt 573 To State Route 622 Bridge
Track Upper Occoquan Sewage Authority 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 Upper Occoquan Sewage Authority Dam
Where does the data for Upper Occoquan Sewage Authority 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 Upper Occoquan Sewage Authority Dam.