DAUPHIN ISLAND, Ala. (AP) — Barriers built with BP money to stop the Gulf oil spill in 2010 could prove effective against storms like Isaac.

That is at least the hope on Dauphin Island, Alabama's largest barrier island, where island and state officials have used money from the oil giant to build dunes and a rock wall. Louisiana officials, meanwhile, have spent more than $200 million on sand berms off their state's coast.

Although the work in Alabama and Louisiana was touted as a way to stop oil from flowing into sensitive marshlands, local officials now see the structures as part of a broader coastal restoration.

Officials are worried that Isaac could stir up tar and oil left behind from the spill, though no one really knows how much remains hidden.