Concerns associated with wetland reclamation are the adverse downstream effects on biodiversity and on the sectors depending on it (e.g. fisheries, tourism).
Today, 116 countries are parties to the Ramsar Convention on Wetlands. It is however very common to see countries committed to this Convention actively supporting wetland reclamation as part of their national agricultural policy. Such inconsistencies are not the result of unwillingness to consider environmental concerns but the consequence of narrow sectoral approaches that fail to integrate coastal resources management.
Besides initial investment costs and future maintenance costs, the major constraints of reclamation are the adverse impact on biodiversity and thus, on the long-term viability of fisheries and waterfowl migrations. These "hidden" effects can be quantified and evaluated through studies that focus on changes of energy and nutrient cycles (i.e. food chain) brought by reclamation works of the past two decades. Careful assessment of the modified hydrological regime will clarify issues such as the longer-term availability of fresh water, expected flood hazards, and waste disposal requirements. Finally, a better understanding of interactions between different sectoral activities (e.g. agriculture, fisheries, tourism, industry) both in terms on impact on the environment and on other sectors' productivity, will shed light on decisions for most suitable land use options.
Wetland contribution to well-being should be established by accounting for return on capital and on labour, return on land, economic variability and risks, market distortions, and distribution of benefits. Information is also needed on past and current resource use patterns by different economic sectors, land tenure of wetlands and surrounding areas, the impact of change in traditional land-use control upon wetland resources, antagonistic or competition over natural resources and economic linkages.
Environmental impact assessment of reclamation, cost-benefit analysis, and economic valuation of wetland functions (e.g. water supply, flood control, waste purification, nutrients pools), products (e.g. fisheries) and attributes (e.g. biodiversity), help establish the short and long-term consequences of existing trends in the condition and use of wetlands.
Wetlands are destroyed where people envisage putting their land and water to a more productive use. This assumption is not valid if efficiency is measured in terms of profit per unit of water and when the cost of the capital investment is taken into account.
The lack of awareness of environmental services or private profit favours wetland drainage, therefore disrupting the normal water supply and compromising long-term viability of investments.
If wetlands are reclaimed for industrial use, and this will result in loss of coastal habitats and nutrients, which in turn will adversely impact fisheries, in a sense, the fishery resources are being allocated to industry.