Author Question: Explain how the construction of a hard stabilization feature (i.e., groin) will force the deposition ... (Read 73 times)

Caiter2013 · **on:** Jul 15, 2018

Explain how the construction of a hard stabilization feature (i.e., groin) will force the deposition of sediment on a coastline.

What will be an ideal response?

Question 2

Rivers in the Pacific Northwest are heavily managed by the construction of dams and reservoirs in order to produce hydroelectric power and, in some areas, for irrigation.

However, the construction of interior dams can have serious consequences for the coastal erosion of beaches and rocky bluffs along the Pacific Coast. How can the construction of these dams lead to the erosion of a rocky coastal bluff?
What will be an ideal response?

cupcake16 · **Reply #1 on:** Jul 15, 2018

Answer to Question 1

Answer: Features like groins, jetties, and breakwaters slow the velocity of the water. When the velocity slows, the water cannot carry sediment as before, and the sediment is deposited.

Answer to Question 2

Answer: Dams trap sediment in the reservoirs that would normally be carried down the stream and jettisoned into the ocean. This sand would help built up a beach in front of the bluffs, forcing the waves to break farther out to sea, away from the bluff. However, without this sand, the beaches are small and easily eroded. Once they are gone, the full-force of the waves crashes against the bluffs.