Question

if a groin is built at p11, on which side will sand accrete?
a. updrift side (south side)
b. downdrift side (north side.)
c. both sides
d. neither side

Explanation:

A groin is a shore protection structure that protrudes into the water. The updrift side (the side from which the long - shore current is coming) will have sand accretion. This is because the groin interrupts the long - shore transport of sediment. The long - shore current moves sediment along the coast. When it encounters the groin, the sediment is deposited on the updrift side as the current loses its ability to carry the sediment past the structure on that side.

Answer:

a. Updrift side (south side)