Potomac Dam No. 5 dam
Potomac Dam No. 5
Potomac Dam No. 5, located in Williamsport, Maryland, is a Federal-owned structure managed by the National Park Service. This earth dam, completed in 1830, serves multiple purposes including providing a fish and wildlife pond, hydroelectric power, and recreational opportunities. With a height of 20 feet and a storage capacity of 4,900 acre-feet, the dam plays a crucial role in managing the flow of the Potomac River and supporting the surrounding ecosystem.
The dam's significant hazard potential and moderate risk assessment highlight the importance of regular inspections and maintenance to ensure its structural integrity and safety. While the last inspection was conducted in September 2015, the dam is regulated by the Maryland Dam Safety agency and the National Park Service, with state permitting, inspection, and enforcement in place. The dam's uncontrolled spillway, with a width of 711 feet, allows for the controlled release of excess water during periods of high flow, protecting downstream areas from potential flooding.
As a key feature in the management of water resources in the region, Potomac Dam No. 5 serves as a vital link in the conservation efforts of the Potomac River. Its role in supporting fish and wildlife habitats, providing recreational opportunities, and contributing to hydroelectric power generation underscores the importance of ongoing monitoring and maintenance to ensure its continued functionality and safety for both the environment and the community.
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 Potomac Dam No. 5 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Conococheague Creek At Fairview | 184 cfs | → |
| Back Creek Near Jones Springs | 22 cfs | → |
| Marsh Run At Grimes | 6 cfs | → |
| Tuscarora Creek Above Martinsburg | 3 cfs | → |
| Opequon Creek Near Martinsburg | 73 cfs | → |
| Potomac River At Shepherdstown | 1,630 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Potomac Dam No. 5.
Boat launches
- Starliper Road Washington County
- Chesapeake And Ohio Canal Trail Washington County
- Blairs Valley Lake
- Taylors Landing
- Snyders Landing Road 17045, Sharpsburg
Campgrounds
- North Mountain Campsite
- North Mountain Hiker Biker Campsite
- Mccoys Ferry Campground
- Mccoys Ferry - C And O Canal National Park
- Jordan Junction Hiker Biker Campsite
- Jordan Junction Campsite
Fishing spots
- Blairs Valley Lake
- Chesapeake And Ohio Canal
- Potomac River Reservoir
- Sideling Hill Creek Put And Take Area
- Hunting Creek Lake
- Fifteenmile Creek
Paddle runs
- Begins South Of Largent To The Confluence With The Potomac At Great Cacapon
- Capon Bridge To Ends Just South Of Largent
- Headwaters Adjacent To Fdt 573 To State Route 622 Bridge
- State Route 675 At Edinburg, Va To State Highway 55 Southeast Of Strasburg, Va
- Wardensville To The Town Of Capon Bridge
- Segment C--Nf Boundary To Confluence With North Fork Shenandoah River
Track Potomac Dam No. 5 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 Potomac Dam No. 5
Where does the data for Potomac Dam No. 5 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 Significant 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 Potomac Dam No. 5.