What would happen if a new shipping channel was cut through a barrier island on the east coast of the U.S. and lined with jetties where there is a strong southward longshore current?
A) The shoreline on the north side would widen seaward, and the one on the south would erode and retreat landward.
B) The shoreline on the south side would widen, and the one on the north would erode and retreat landward.
C) Both shorelines would retreat.
D) Neither shoreline would retreat.
E) All of the barrier islands would disappear because of erosion.

Question

Quizplus · Accepted Answer

The construction of a shipping channel through a barrier island, especially when accompanied by jetties, disrupts the natural flow of sediments due to the longshore current. In this scenario, with a strong southward longshore current, sediment transport is interrupted by the jetties. Sediments that would normally be carried southward are trapped on the north side of the jetties, causing the shoreline on the north side to accumulate sediments and widen seaward. Conversely, the shoreline on the south side of the jetties receives less sediment because the jetties block the natural flow, leading to erosion and a retreat of the shoreline landward.

What Would Happen If a New Shipping Channel Was Cut