New Holland Reservoir dam
New Holland Reservoir
New Holland Reservoir, located in Lancaster, Pennsylvania, was completed in 1953 and serves as a vital source of water supply for the area. This private earth dam stands at a height of 40 feet and has a length of 670 feet, with a storage capacity of 165 acre-feet. The reservoir covers an area of 8.3 acres and is fed by the TR Mill Creek, contributing to its drainage area of 1.1 square miles.
Managed by the Pennsylvania Department of Environmental Protection, New Holland Reservoir is regulated, inspected, and enforced to ensure its safety and functionality. Despite being classified as having a high hazard potential, the dam is currently in fair condition as of the last inspection in December 2020, with an inspection frequency of once per year. The reservoir plays a crucial role in providing water to the surrounding community while also posing certain risks that need to be managed effectively.
For water resource and climate enthusiasts, New Holland Reservoir represents a fascinating example of infrastructure that supports both human needs and environmental considerations. With its strategic location in East Earl Township and the oversight of state regulatory agencies, this reservoir offers a glimpse into the complex interplay between water management, dam safety, and the importance of sustainable practices in ensuring a reliable water supply for the future.
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 New Holland Reservoir -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Pequea Creek Near Ronks | 69 cfs | → |
| West Branch Brandywine Creek Near Honey Brook | 9 cfs | → |
| Birch Run Near Wagontown | 2 cfs | → |
| West Branch Brandywine Creek At Coatesville | 26 cfs | → |
| Conestoga River At Lancaster | 159 cfs | → |
| West Branch Brandywine Creek At Modena | 37 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near New Holland Reservoir.
Boat launches
- Struble Lake
- Stone Quarry Road 101, Lancaster County
- Chambers Lake
- Hopewell Lake-French Creek State Park
- Scott's Run Lake-French Creek State Park
- West Side-Lyndell
Campgrounds
- Red Run Campground
- Mill Bridge Village Camp Resort
- William Penn State Forest Designated Campsite
- Refreshing Mountain Retreat And Adventure Center
- Harmony Hill Wilderness Area Campsite
- Camp Conquest
Fishing spots
Track New Holland Reservoir 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 New Holland Reservoir
Where does the data for New Holland Reservoir 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 New Holland Reservoir.