Mongaup River

Last Updated: May 11, 2026

Total streamflow across the Mongaup River was last observed at 206 cfs, and is expected to yield approximately 409 acre-ft of water today; about 36% of normal. River levels are low and may signify a drought. Average streamflow for this time of year is 573 cfs, with recent peaks last observed on 2021-10-28 when daily discharge volume was observed at 4,956 cfs.

Maximum discharge along the river is currently at the Mongaup River At Mongaup Valley Ny reporting a streamflow rate of 206 cfs. This is also the highest stage along the Mongaup River, with a gauge stage of 3.7 ft at this location. This river is monitored from 2 different streamgauging stations along the Mongaup River, the highest being situated at an altitude of 1,069 ft, the Mongaup River At Mongaup Valley Ny.

The Mongaup River is a 20-mile-long river located in Sullivan and Orange Counties in New York.


15-Day Long Term Forecast


River Details

Last Updated 2026-05-11
Discharge Volume 409 ACRE-FT
Streamflow 206.0 cfs
Past 24 Hours: -118.0 cfs (-36.42%)
Percent of Normal 35.96%
Maximum 4,956.0 cfs
2021-10-28
Seasonal Avg 573 cfs
       
River Streamflow Levels
Streamgauge Streamflow Gauge Stage 24hr Change (%) % Normal Minimum (cfs) Maximum (cfs) Air Temp Elevation
Mongaup River At Mongaup Valley Ny
USGS 01432900
206 cfs 3.7 ft -36.42
Mongaup River Near Mongaup Ny
USGS 01433500
188 cfs 1.83 ft -2.08
Seasonal Discharge Comparison
Maximum Streamflow Discharge
Streamflow Elevation Profile

Mongaup River is a stream in the U.S. state of New York. It is a tributary to the Delaware River.
Mongaup is a name derived from an Indian language meaning perhaps "dancing feather" or "huckeberry valley". Variant spellings have been "Mangawping River", "Mingwing River", "Mon-gaw-ping River" and "Mongaap River".