Glen Elyn Lower Dam (Forest Glen Drive) dam
Glen Elyn Lower Dam (Forest Glen Drive)
Glen Elyn Lower Dam, located in the Moores Road Area of Harford, Maryland, is a recreational Earth dam built in 1975 with a height of 21.5 feet and a hydraulic height of 17 feet. The dam serves primarily for recreation purposes, providing a surface area of 1.8 acres and a normal storage capacity of 8.5 acre-feet. The dam is situated on the Little Gunpower Falls-TR river, within the Philadelphia District of the US Army Corps of Engineers.
Despite being categorized as having a significant hazard potential, Glen Elyn Lower Dam is assessed to be in fair condition as of April 2021. The dam underwent structural modifications in 2009 and is inspected every three years. Its spillway type is uncontrolled, with a maximum discharge capacity of 170 cubic feet per second. The dam is regulated by the Maryland Dam Safety agency and has state permits for operation, inspection, and enforcement.
Overall, Glen Elyn Lower Dam is a vital recreational structure in the Moores Road Area, offering opportunities for water-based activities and leisure. With its moderate risk assessment and fair condition, the dam continues to be an important feature for water resource and climate enthusiasts to appreciate and monitor for safety and regulatory compliance.
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 Glen Elyn Lower Dam (Forest Glen Drive) -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Little Gunpowder Falls At Laurel Brook | 26 cfs | → |
| Long Green Creek At Glen Arm | 5 cfs | → |
| Gunpowder Falls At Glencoe | 124 cfs | → |
| Winters Run Near Benson | 27 cfs | → |
| Little Falls At Blue Mount | 62 cfs | → |
| Beaverdam Run At Cockeysville | 31 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Glen Elyn Lower Dam (Forest Glen Drive).
Track Glen Elyn Lower Dam (Forest Glen Drive) 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 Glen Elyn Lower Dam (Forest Glen Drive)
Where does the data for Glen Elyn Lower Dam (Forest Glen Drive) 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 Glen Elyn Lower Dam (Forest Glen Drive).