Coastal zone under siege - Is there realistic relief available?

The coastal zone has been-and is-under siege from several angles for years. The shoreline, in most areas of the world is subject to erosion and regresses. The waters bathing it have been, and continue to be, polluted, mostly anthropogenically, and mainly due to agricultural practices. The coastal zone is, and will be even more intensely, under pressure from a population shift. It is wanted by industry, trade, tourism. These wants and uses are often in conflict with one another, and just as often not sustainable. What can the coastal zone manager and the decision-maker realistically do so that the heritage of mankind be passed on in a tolerable condition? What can be done so that economic development not be stymied and yet such development be sustainable