Similarly to Crawford Notch to the east, the main body of Zealand Notch comprises a steep-walled, U-shaped valley running southwards from the height of land. Whitewall Brook flows through the bottom of the notch, reaching the North Fork of the Pemigewasset River at the south end of the notch. Water from Whitewall Brook flows via branches and the main stem of the Pemigewasset to the Merrimack River and ultimately the Gulf of Maine. North of the notch's height of land, the Zealand River flows north to the Ammonoosuc River near the village of Twin Mountain, with the streamflow eventually reaching the Connecticut River and turning south again to ultimately reach Long Island Sound.