Hurricane Rita devastated gulf-front communities along the western Louisiana coast in 2005. LIDAR (light detection and ranging) topographic surveys and aerial photography collected before and after the storm showed the loss of every structure within the community of Holly Beach. Average shoreline change along western Louisiana's 140-km-long impacted shore was −23.3 ± 30.1 m of erosion, although shoreline change in Holly Beach was substantially less, and erosion was not pervasive where the structures were lost. Before the storm, peak elevations of the dunes, or berms in the absence of dunes, along the impacted shore averaged 1.6 m. The storm surge, which reached 3.5 m just east of Holly Beach, completely inundated the beach systems along the impacted western Louisiana shore. The high surge potential and low land elevations make this coast extremely vulnerable to hurricanes. In fact, most of the western Louisiana shore impacted by Rita will be completely inundated by the storm surge of a worst-case Saffir-Simpson category 1 hurricane. All of this shore will be inundated by worst-case category 2–5 storms.

The Sabine-Neches fluvial-estuary system is composed of deposits that represent fluvial, deltaic, central-basin, tidal inlet/delta, and chenier depositional systems. The Holocene deposits and associated environmental changes preserved in the drowned Sabine-Neches alluvial valley provide a valuable analog for present and future environmental changes. These deposits are bounded by flooding surfaces that record episodes of dramatic environmental reorganization during the Holocene. The most dramatic environmental changes are manifested as stratigraphic back stepping in which central-basin sediments overlie deltaic sediments. The magnitude of flooding varies from a few tens of kilometers to less pronounced back stepping followed by rapid progradation. Initial flooding of the onshore Sabine-Neches incised valley occurred around 9800 cal yr B.P., and by ca. 8900 cal yr B.P., a vast bayhead delta occupied the southern half of the valley. This delta backstepped up the valley during the relatively rapid sealevel rise of the early to middle Holocene, and by ca. 7100 cal yr B.P., it occupied the entire valley. After ca. 7100 cal yr B.P., the bayhead delta shifted up the valley again, and a central-basin setting existed in the lower half of the valley. The middle basin expanded episodically between ca. 5500 cal yr B.P. and 1700 cal yr B.P., and a brief period of delta growth occurred ~300 yr ago. Controlling mechanisms for flooding surface formation include sea-level rise, changes in the antecedent topography of the incised valley, and sediment supply variations. Antecedent topography was influential in controlling estuarine evolution between ca. 7800 and 7500 cal yr B.P., when an extensive fluvial terrace was inundated. The fact that some flooding surfaces appear to be synchronous, within a few centuries, in several estuaries across the northern Gulf of Mexico suggests a eustatic rather than local control. Flooding events at ca. 8900 cal yr B.P. and ca. 8400–8000 cal yr B.P. were likely caused by rapid, sub–meter-scale sea-level rise events. Sediment supply variations controlled by climatic forcing appear to have been the main cause of other flooding events. Unfortunately, the Holocene climate record for the east Texas–west Louisiana coastal region is poorly documented, and a direct relationship to central and western Texas climate records may be complex. So the exact nature of climate control on sediment flux to the estuary system remains elusive.

Abstract Each year from June through November, tropical cyclones are a common potential problem for those living in coastal communities along the southwest Louisiana and southeast Texas coasts. Developing from small tropical disturbances, tropical cyclone strength is determined by many factors: ocean temperature, upper and lower wind circulation, latitudinal position, etc. Ecological, geological, and economic effects of strong-to-devastating tropical cyclones on coastal areas are typically extreme. Since the 1860s, seven strong or greater tropical cyclones have struck the Louisiana-Texas coast. Their impact has made an indelible impression on the coastline as well as on the communities in the area