Reply The Great Swamp Watershed Association acquired 10 acres of open space in Chatham Township. (Shutterstock) CHATHAM, NJ — The Great Swamp Watershed Association acquired 10 acres of open space in Chatham Township. Thanks to a family's donation, the environmental organization now holds 86.5 preserved acres in the Great Swamp watershed. The space is located at the end of Evergreen Road in the Black Brood sub-watershed — one of the five sub-watersheds in the Great Swamp. The property connects to a large amount of preserved open space, which includes the Great Swamp National Wildlife Refuge, along with a 3.5-acre tract of land known as the Hoag Property that the watershed association acquired 20 years ago.