Greenwich Township is the westernmost township in Cumberland County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 771, a decrease of 33 from the 2010 census count of 804, which in turn reflected a decline of 43 from the 847 counted in the 2000 census. It is part of the Vineland-Bridgeton metropolitan s…Greenwich Township is the westernmost township in Cumberland County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 771, a decrease of 33 from the 2010 census count of 804, which in turn reflected a decline of 43 from the 847 counted in the 2000 census. It is part of the Vineland-Bridgeton metropolitan statistical area, which encompasses those cities and all of Cumberland County for statistical purposes and which constitutes a part of the Delaware Valley.