Goat Island (New York) - Geology

Geology

The island was formed geologically during the recent retreat of the falls as it cuts inward (upstream) through the Niagara Escarpment. The channel of the Niagara River splits in two above the falls, creating two sets of falls, one on either side of the island. In 1959-60, the eastern side of the island was extended about 8.5 acres (34,000 m2) for additional parking and a helicopter pad. Fill was provided from excavation for the construction of the Robert Moses State Parkway. In 1955 the area between the Terrapin Rocks and Goat Island was filled in, creating Terrapin Point.

In the early 1980s the United States Army Corps of Engineers filled in more land and built diversion dams and retaining walls to force the water away from Terrapin Point. Altogether 400 feet (120 m) of the Horseshoe Falls was eliminated, including 100 feet (30 m) on the Canadian side. According to author Ginger Strand, the Horseshoe Falls is now entirely in Canada. Other sources say "most of" Horseshoe Falls is in Canada.

The western end of the island is slowly being eroded by the falls and the entire island will eventually disappear as the falls erode further upstream. The waters immediately around Goat Island are relatively shallow and studded with islets and rocks, many of them scenes of dramatic rescues and rescue attempts.