Casselman River River Levels

Last Updated: December 4, 2025

The Casselman River is a 56-mile long tributary of the Youghiogheny River located in western Maryland.


Summary

Total streamflow across the Casselman River was last observed at 169 cfs, and is expected to yield approximately 336 acre-ft of water today; about 24% of normal. River levels are low and may signify a drought. Average streamflow for this time of year is 692 cfs, with recent peaks last observed on 2025-05-14 when daily discharge volume was observed at 29,280 cfs.

Maximum discharge along the river is currently at the Casselman River At Markleton reporting a streamflow rate of 132 cfs. This is also the highest stage along the Casselman River, with a gauge stage of 1.1 ft at this location. This river is monitored from 2 different streamgauging stations along the Casselman River, the highest being situated at an altitude of 2,135 ft, the Casselman River At Grantsville.

River Details

Last Updated 2025-12-04
Discharge Volume 336 ACRE-FT
Streamflow 169.4 cfs
-0.2 cfs (-0.12%)
Percent of Normal 24.48%
Maximum 29,280.0 cfs
2025-05-14
Seasonal Avg 692 cfs
       
River Streamflow Levels
Streamgauge Streamflow Gauge Stage 24hr Change (%) % Normal Minimum (cfs) Maximum (cfs) Air Temp Elevation
Casselman River At Grantsville
USGS 03078000
37 cfs 1.1 ft 26.35
Casselman River At Markleton
USGS 03079000
132 cfs 1.1 ft -5.71
Seasonal Discharge Comparison
Maximum Streamflow Discharge
Streamflow Elevation Profile

The Casselman River is a 56.5-mile-long (90.9 km) tributary of the Youghiogheny River in western Maryland and Pennsylvania in the United States.The Casselman River rises in Garrett County atop the plateau of western Maryland as two branches, the south one east of Meadow Mountain, the north one farther west, between Meadow Mountain and Negro Mountain. The two branches flow northward combining just southwest of Grantsville, Maryland. The river then continues north into Pennsylvania, following a great arc across the Laurel Highlands of Somerset County, Pennsylvania to the community of Confluence, where Laurel Hill Creek joins a few meters above the Youghiogheny River.The river has been used for transportation across the Allegheny Mountains, between the cities of Baltimore and Washington, D.C. in the east and Pittsburgh in the west. Two railroads followed the Casselman River from Meyersdale, Pennsylvania to Confluence. First is the B&O Railroad, running between Baltimore and Pittsburgh, which was completed in 1827, and is currently owned by CSX. Second is the Western Maryland Railway, which ran from Cumberland, Maryland to Connellsville, Pennsylvania. Although the Western Maryland was abandoned in the 1980s, the right-of-way has been converted into the Great Allegheny Passage, a rail trail bicycle and hiking path.