South River is a city located in the New Jersey region of the United States. During the most recent census, South River had a population of 16,008. South River is the 102nd most poplulated city in the New Jersey region, the 2,690th most populated city in the United States and the 15,918th most populated city in the world. South River is in the America/New York timezone which is 4 hours behind UTC. South River adjusts the hour with daylight savings time during the winter months.