Presque Island State Park PA?

Question

What is the direction of the longshore current? Also, at the end of winter why does sand connect some of the breakwaters to the beach?

Answer 1

The long shore currents flow flow from west to east, pushed by the wind. Sand has been trucked from the eastern end of the spit back to the neck to keep the neck from eroding away. The entire spit, which is what Presque Isle is, would migrate entirely to the east if not for the intervention of man. It would move off the shelf it is located on and disappear into Lake Erie.

The break waters cause the wind driven waves to lose their energy and it disrupts the easterly long shore currents. When the currents and waves lose energy, they lose their ability to transport sand, so it drops out behind the break waters.

Presque Isle is a very unique geological anomaly. There are lots of studies on Presque Isle, check your library.

Did you know that Lake Erie is about 1.5 feet higher on its American shores than it is on its Canadian shores? The prevailing westerly winds push the water across the Lake and piles it up on the American shore.