Piney Run Dam dam
Piney Run Dam
Piney Run Dam, also known as Lake Werowance, is a privately owned earth dam located in Fairfax, Virginia, along the Piney Run river. Standing at 15 feet tall and 180 feet long, this dam serves a primary purpose that is categorized as 'Other'. With a maximum storage capacity of 167 acre-feet and a normal storage of 58 acre-feet, Piney Run Dam plays a crucial role in water resource management in the area.
The dam's hazard potential is currently labeled as 'Undetermined', with its condition assessment marked as 'Not Rated'. Despite this, the structure has not undergone recent inspections and lacks a formal emergency action plan. As a water resource and climate enthusiast, one may find Piney Run Dam to be an interesting case study in terms of its design, purpose, and maintenance practices. Its location in a highly populated area like Fairfax highlights the importance of proper management and monitoring of such critical infrastructure.
With its unique characteristics and uncertain hazard potential, Piney Run Dam presents an intriguing subject for further exploration and analysis in the realm of water resource and climate studies. As a privately owned structure in Virginia, its role in ensuring water supply, flood control, and environmental protection underscores the need for ongoing assessment and regulation to safeguard the surrounding community and ecosystem.
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 Piney Run Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Difficult Run Near Great Falls | 12 cfs | → |
| Potomac River Near Wash | 2,300 cfs | → |
| Broad Run Near Leesburg | 21 cfs | → |
| Seneca Creek At Dawsonville | 40 cfs | → |
| Accotink Creek Near Annandale | 3 cfs | → |
| Long Branch Near Annandale | 0 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Piney Run Dam.
Boat launches
- Potomac Hills Street Fairfax County
- Rileys Lock Road Darnestown
- Ashburn Village Boulevard 20585, Lansdowne
- Edwards Ferry Road Montgomery County
- Clarksburg Road Germantown
- Gravelly Point Boat Ramp
Campgrounds
- Lake Fairfax
- Marsden Tract Group Campsite
- Marsden Tract Campground
- Swains Lock Hiker-Biker Campsite
- Horsepen Branch
- Horsepen Branch Campsite
Fishing spots
- Washington Aqueduct
- Dalecarlia Reservoir
- Gillam Branch (Historical)
- Davis Branch (Historical)
- Maddox Branch
- Georgetown Reservoir
Track Piney Run 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 Piney Run Dam
Where does the data for Piney Run 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 Undetermined 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 Piney Run Dam.