Final answer:
The Hudson River is the only entirely fresh water river in New York City.
Step-by-step explanation:
The only entirely fresh water river in New York City is the Hudson River. The river runs for about 315 miles and is primarily fed by rainfall and snowmelt. It serves as an important waterway for commerce and transportation in the region. The Hudson River is known for its scenic beauty and plays a significant role in the history and development of New York City.