Wetland loss in the Mississippi Delta Plain is attributable to alterations in flooding patterns and sediment supply at a number of scales. Contributing factors include the placement of flood control levees along the River itself, isolating the delta plain from its natural source of sediment and freshwater, as well as the smaller scale but very common construction of spoil banks along the extensive network of canals dredged for oil and gas exploration. Opportunities for addressing the results of these changes vary across the delta plain. In some areas within the 'birdsfoot delta' below the flood control levees, artificial 'crevasses' (cuts in the natural river levee) have been created. These have resulted in emergent marsh formation within about 2 years of breaching, with an average land gain of nearly 5 ha yr^-1. The cost of each crevasse averaged around US$20,000. Thus these schemes prove cost-effective relative to larger and more complex projects higher on the river where project costs must include the relocation of infrastructure such as roads and railways as well as the engineering challenge of making a controlled breach in major flood control levee. While cost effective, the artificial crevasses represent a technique which has limited application geographically and that creates new habitat in areas remote from hurricane protection levees and human infrastructure where the need for conservation is perhaps greatest. Larger river diversions through controlled structures are under construction and more are planned as the keystone action in a new strategic plan for the provision of sustainable coastal resources in Louisiana.

For sites remote from river distributaries with readily breachable levees, managed dredge material disposal offers an alternative means of increasing wetland elevations. However, sediment recharges need to be carefully managed if they are to have the desired ecological effects. In particular, the thickness of material placement controls the mechanism of vegetative recolonisation. One means of ensuring recolonisation within existing marshes subject to rapid submergence is thin-layer deposition using a spray-dredging technique. The technique has also proved successful in raising the elevation of adjacent shallow pond environments (caused by deterioration of saltmarsh to open water). Thus within the Mississippi delta plain opportunities exist for salt marsh conservation concurrent with continuing industrial and commercial development. While industrial development within the coastal zone caused many problems for coastal salt marshes, increased understanding of salt marsh value and threats to its sustainability mean that not that dredging and development have been halted - rather that dredged material is now used to improve and sustain otherwise degrading habitats.