Island Pond is a 532-acre water body located in Rockingham County in southern New Hampshire, in the towns of Derry, Hampstead and Atkinson. The pond is at the head of the Spicket River watershed, which feeds into the Merrimack River in Lawrence, Massachusetts. The pond was formed from the merger of Perch Pond in Hampstead and Lake Wentworth i…Island Pond is a 532-acre water body located in Rockingham County in southern New Hampshire, in the towns of Derry, Hampstead and Atkinson. The pond is at the head of the Spicket River watershed, which feeds into the Merrimack River in Lawrence, Massachusetts. The pond was formed from the merger of Perch Pond in Hampstead and Lake Wentworth in Derry in 1878, when a new dam raised the water level by 8.5 feet.