The Mongaup River is a scenic waterway in southeastern New York that flows approximately 10 miles from its source at the Rio Dam to its confluence with the Delaware River near Port Jervis. This river system, fed by releases from upstream reservoirs, offers exciting whitewater opportunities for intermediate paddlers. The most popular paddling section runs 2.9 miles from Rio Dam to the Delaware River confluence. This stretch features Class II-III rapids, making it suitable for kayakers and canoeists with some whitewater experience. The run begins with technical boulder gardens before opening up into wave trains and playful features. A notable landmark is the Rio Main Powerhouse, located about halfway through the run.

Paddling opportunities on the Mongaup are largely dependent on scheduled releases from Rio Dam. Recreational releases typically occur on weekends from April through October, with additional power generation releases providing more frequent paddling options. The river is closed to paddling from December 1 to April 1 to protect nesting bald eagles. Access to the put-in at Rio Dam is via a steep path, so paddlers should be prepared for a bit of a hike. The main take-out is at the confluence with the Delaware River, though some paddlers continue downstream on the Delaware to Port Jervis. Nearby towns include Forestburgh and Sparrowbush.

The Mongaup River valley hosts diverse wildlife, including bald eagles, black bears, and various fish species. The surrounding forests showcase a mix of hardwoods and evergreens typical of the Catskill region.

For those seeking a longer adventure, the Mongaup can be combined with sections of the Delaware River for multi-day trips. Popular options include continuing from the Mongaup confluence down to Matamoras, PA, which adds about 6 miles of Class I-II water with scenic views of the Delaware Water Gap.

Safety considerations include cold water temperatures from dam releases and potential strainers in the narrower upper sections. Paddlers should check release schedules and water levels before their trip. While not overly technical, the Mongaup's consistent flow and variety of features make it an excellent training ground for developing whitewater skills in a relatively controlled environment.