Dam Report

Blue Marsh Dam dam

Pennsylvania, USA Tulpehocken Creek Hazard High
Today high
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Tonight low
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Dam height
100ft
Hazard rating
High
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Blue Marsh Dam -- None dam
Blue Marsh Dam None · Tulpehocken Creek
About this dam

Blue Marsh Dam

Blue Marsh Dam, located in Reading, Pennsylvania, was completed in 1977 by the US Army Corps of Engineers for the primary purpose of flood risk reduction. Standing at a structural height of 100 feet and with a hydraulic height of 94 feet, the dam plays a crucial role in protecting downstream communities such as Reading, Birdsboro, Pottstown, and Philadelphia from potential flooding events. With a storage capacity of 129,900 acre-feet and a drainage area of 175 square miles, the dam can handle a maximum discharge of 70,000 cubic feet per second.

Despite being classified as having a "Moderate" risk level, the US Army Corps of Engineers implements rigorous risk management measures to ensure the safety and stability of Blue Marsh Dam. Regular inspections, monitoring, and maintenance are conducted to identify any signs of deterioration or potential issues. Emergency repair materials are stocked nearby in case of dam seepage, and staff closely monitor weather forecasts to prepare for possible flood events. Additionally, the Corps collaborates with state and county emergency management officials to conduct emergency exercises and ensure a coordinated response in case of an emergency.

The risk assessment for Blue Marsh Dam is based on the potential for the reservoir level to rise high enough during intense rainfall events, potentially causing erosion that could lead to a breach and subsequent flooding downstream. By closely monitoring the dam's performance and implementing proactive measures, the US Army Corps of Engineers is dedicated to safeguarding the surrounding communities and ensuring the structural integrity of Blue Marsh Dam.

StateNone
River / streamTulpehocken Creek
NID IDPA00921
Owner typeFederal
Primary purposeFlood Risk Reduction
Dam typeRockfill
Year built1977
Dam length1,775 ft
Max storage129,900 AF
Normal storage22,897 AF
Surface area1,147.0 ac
Drainage area175.0 sq mi
Hazard potentialHigh
ConditionNot Available
Last inspectionThu, 02 May 2019 00:00:00 GMT
EAP preparedYes

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 Blue Marsh Dam -- inflows here typically show up in storage 24-72 hours later.

Track Blue Marsh 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.

FAQ

About Blue Marsh Dam

Where does the data for Blue Marsh 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 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.