Spring Valley, incorporated on July 9, 1902, is a village in the towns of Ramapo and Clarkstown in Rockland County, New York, United States. It is located north of Chestnut Ridge, east of Airmont and Monsey, south of Hillcrest, and west of Nanuet. The population was 31,347 at the 2010 census, making it the 2nd most populous community in Rockland County, after New City.