Blue Marsh Lake is managed by U.S. Army Corps of Engineers. Lake Insights displays its latest available elevation from U.S. Geological Survey. Published reference elevations are listed below.
Lake Status
At full pool
- 7-day trend
- Rising
- 7-day change
- Up 0.03 ft
- 30-day change
- Up 0.02 ft
- Last updated
- 4 hours ago
Blue Marsh Lake is currently near full pool and has risen slightly over the past week. Levels have been climbing toward full pool over the past week.
Watershed drought conditions
Berks County, PA · surrounding county from lake location
Abnormally Dry
The surrounding county is abnormally dry, which is not official drought.
Severity
Weekly trend
Improving
Compared with last week
Official drought
No
Current conditions are classified as Abnormally Dry (D0), which is not considered official drought.
U.S. Drought Monitor · map date Sep 22, 2026. Updated weekly. droughtmonitor.unl.eduView drought map for Berks County, PA
Key Facts
Managing authority
Waterbody / project type
Official purposes
Full pool
Winter pool
Current-level source
Project / NID identifier
Dam / watershed (NID design values)
Static design values from a confidently matched National Inventory of Dams record — not live gage readings.
- Normal storage
- 22,897 acre-ft
- Max storage
- 129,900 acre-ft
- Surface area at normal pool
- 1,147 acres
- Drainage area
- 175 sq mi
- Spillway capacity (design)
- 70,000 cfs
- Dam structure
- Rockfill · 100 ft high · completed 1977
- Hazard classification
- High
- Safety & inspection
- last inspection Jun 10, 2024 · EAP yes
National Inventory of Dams · matched record: Blue Marsh Dam (PA00921)
How this lake is operated
- Documented project purposes (National Inventory of Dams): Flood Risk Reduction, Recreation, Water Supply.
Why the level can change
General factors for reservoirs like this
These are common influences for this type of lake. They do not identify the cause of a specific current change unless an operator update confirms it.
Rainfall & inflows
Rain and upstream river inflows can raise reservoir levels, especially after storms.
Downstream releases
When an operator releases water through a dam, reservoir storage can fall and downstream flows can rise.
Flood-risk operations
Some projects store or release water under flood-risk rules when conditions require it.
Water supply
Some reservoirs support municipal, industrial, irrigation, or regional water-supply needs.
Hydropower
Hydropower projects may pass water through turbines when generating electricity.
Seasonal weather
Dry periods, heat, evaporation, and seasonal rainfall patterns can affect storage over weeks and months.
Published reference elevations
- Full pool
- 290.00 ft
- Winter / seasonal pool
- 285.00 ft
Published reference elevation. Not necessarily a fixed year-round target for every project.
A winter / seasonal pool elevation is published, but Lake Insights does not have verified seasonal operating dates for this lake.
Current data source
Managing authority: U.S. Army Corps of Engineers
Observation source used by Lake Insights: U.S. Geological Survey
Who manages the lake and who publishes the reading Lake Insights displays can differ. Lake Insights does not invent a source label from the managing authority alone.
General education
Shared background — not lake-specific facts
Lake Insights aggregates water level information from authoritative public sources such as the U.S. Army Corps of Engineers, NOAA, TVA, Bureau of Reclamation, power utilities, and other official lake operators. We preserve historical observations, calculate trends, and present lake conditions in a consistent format. For U.S. Geological Survey, we link to the official source whenever it is available. Lake Insights does not predict future lake levels unless an official forecast has been published by the managing authority.
Common questions about Blue Marsh Lake
- Who manages Blue Marsh Lake?
- Blue Marsh Lake is managed by U.S. Army Corps of Engineers. Lake Insights reports published gauge readings; it does not operate the waterbody.
- What is full pool at Blue Marsh Lake?
- The published full-pool elevation for Blue Marsh Lake is 290.00 ft. Full pool is a published reference elevation — not a prediction of today’s level.
- Does Blue Marsh Lake have a published winter pool?
- Blue Marsh Lake has a published winter / seasonal pool elevation of 285.00 ft. Lake Insights does not currently have verified seasonal operating dates for this lake.
- Where does Lake Insights get the level reading for Blue Marsh Lake?
- Lake Insights displays the latest available elevation for Blue Marsh Lake from U.S. Geological Survey. The managing authority (U.S. Army Corps of Engineers) may differ from the agency that publishes the observation used on this page.
- What are the documented purposes of Blue Marsh Lake?
- Documented purposes for Blue Marsh Lake (National Inventory of Dams): Flood Risk Reduction, Recreation, Water Supply.