Before revision: Marsh terracing is most common throughout the upper Gulf Coast where it is used to prevent coastal erosion, with 980 linear km (609 mi) having been built in Texas and Louisiana alone over the past thirty years .
After revision: Marsh terracing is most common throughout the upper Gulf Coast where it is used to prevent coastal erosion, with 980 linear km (609 mi) having been built in Texas and Louisiana alone of the United States,