Dam Report

Green Lane Reservoir dam

Pennsylvania, USA Perkiomen Creek Hazard High
Today high
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Tonight low
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Dam height
87ft
Hazard rating
High
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Green Lane Reservoir -- None dam
Green Lane Reservoir None · Perkiomen Creek
About this dam

Green Lane Reservoir

Green Lane Reservoir, located in Montgomery County, Pennsylvania, is a gravity dam completed in 1957 primarily for water supply purposes. With a height of 87 feet and a storage capacity of 25,114 acre-feet, this reservoir on the Perkiomen Creek serves as a vital source of water for the region. The dam is owned by a private entity but is regulated by the Pennsylvania Department of Environmental Protection, ensuring that it meets state inspection and enforcement standards.

Despite its age, Green Lane Reservoir maintains a satisfactory condition assessment and has a high hazard potential due to its location and storage capacity. The reservoir also offers recreational opportunities in addition to its water supply function, with a surface area of 814 acres for activities like boating and fishing. The dam's emergency action plan status and risk management measures are currently unspecified, highlighting the need for continued monitoring and maintenance to ensure the safety and sustainability of this essential water resource in the face of evolving climate challenges.

StateNone
River / streamPerkiomen Creek
NID IDPA00618
Owner typePrivate
Primary purposeWater Supply
Dam typeGravity
Year built1957
Dam height87 ft
Dam length780 ft
Max storage25,114 AF
Normal storage13,430 AF
Surface area814.0 ac
Drainage area71.0 sq mi
Hazard potentialHigh
ConditionSatisfactory
Last inspectionMon, 09 Nov 2020 00:00:00 GMT

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.
Detailed forecast

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.

Hourly detail

Next 5 days, hour by hour

Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.

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Deep dive

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.

TimeConditionTemp (°F)Snow (in)Rain (in)Humidity (%)Wind (mps)Wind dir
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Long-term outlook

15-day temperature & precipitation

Daily temperatures, snow, and rain projected over the next two weeks.

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Regional inflow

Nearby streamflow gauges

USGS streamgauges around Green Lane Reservoir -- inflows here typically show up in storage 24-72 hours later.

Track Green Lane 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.

FAQ

About Green Lane Reservoir

Where does the data for Green Lane 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.