Aguadilla, Puerto Rico

CLIENT: US Army Corps of Engineers

STA RESULTS: Transport pathways and their dynamic behaviour revealed

  • Sand being trapped behind the breakwater did not come from a southward littoral drift transport regime as assumed during its design and placement. 
  • Sand moves southwards down the coastline in a series of counterclockwise gyres. The source of the sand behind the breakwater is from the offshore in the deep waters of the Mona Passage – the channel separating Puerto Rico from the Dominican Republic.
  • The offshore sand is transported southwards due to strong ocean currents. The breakwater blocks the local counterclockwise gyre resulting in sand deposition that is unable to return to the deep water.
  • As the amount of sand trapped behind the breakwater is small compared to the offshore source, it is not responsible for the erosion known to be occurring in the bay to the south of Aguadilla.