Total streamflow across the Mongaup River was last observed at 376 cfs, and is expected to yield approximately 746 acre-ft of water today; about 66% of normal. River levels are low and may signify a drought. Average streamflow for this time of year is 569 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 Near Mongaup Ny reporting a streamflow rate of 213 cfs. However, the streamgauge with the highest stage along the river is the Mongaup River At Mongaup Valley Ny with a gauge stage of 3.64 ft. 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. The river starts at the Mongaup Pond in the Catskill Mountains and flows into the Delaware River. The Mongaup River has a rich history, having been used for logging and fishing in the past. The river is also an important source of drinking water for several communities. The river has several reservoirs and dams, including the Rio Dam and the Mongaup Falls Reservoir. These reservoirs help regulate the flow of the river and provide hydroelectric power. The Mongaup River is a popular destination for recreational activities such as fishing, kayaking, and camping. The river is also used for agricultural purposes, including irrigation and livestock watering.