Grigg Lake Dam dam
Grigg Lake Dam
Grigg Lake Dam, located in Powhatan, Virginia, serves as a crucial water resource for the surrounding area. Built primarily for recreation purposes, this earth dam stands at a height of 21 feet and has a storage capacity of 321 acre-feet. Situated on Mohawk Creek, the dam is owned and regulated by the Virginia Department of Conservation and Recreation, ensuring that it meets all necessary state permitting, inspection, and enforcement requirements.
Despite its importance as a recreational water source, the condition of Grigg Lake Dam remains undetermined, with an unclassified hazard potential and no formal assessment rating. The dam has not been recently inspected or assessed for its emergency action plan readiness, leaving some uncertainty about its overall safety and risk management measures. This lack of updated information underscores the need for continued monitoring and maintenance to ensure the dam's reliability in the face of changing climate conditions and potential environmental risks.
As climate change continues to impact water resources and infrastructure across the country, it is essential for enthusiasts and stakeholders to stay informed about the status of dams like Grigg Lake Dam. By advocating for regular inspections, risk assessments, and emergency preparedness measures, we can help safeguard this important water resource for future generations and ensure its resilience in the face of evolving environmental challenges.
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 Grigg Lake Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Fine Creek At Fine Creek Mills | 2 cfs | → |
| James River At Cartersville | 1,580 cfs | → |
| Appomattox River At Mattoax | 115 cfs | → |
| James River And Kanawha Canal Near Richmond | 137 cfs | → |
| James River Near Richmond | 1,230 cfs | → |
| South Anna River Near Ashland | 34 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Grigg Lake Dam.
Boat launches
- Bateau Landing Road 4399, Powhatan County
- Powhatan State Park Road Powhatan County
- River Trail Powhatan County
- River Launch Road Powhatan County
- Mill Mount Trail Powhatan County
- Watkins Landing Road 3099, Powhatan County
Track Grigg Lake 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 Grigg Lake Dam
Where does the data for Grigg Lake 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 Grigg Lake Dam.