In the last decade an important discussion has taken place in the Netherlands concerning the creation of Markerwaard, a polder (an area of new land reclaimed from below sea level) in the Ijsselmeer (the former Zuider Zee). In the deliberations, a number of certainties crossed the discussion tables. The engineers who had recently worked on previous Ijsselmeer polders were sure that they would be able to create a beautiful new polder, which would give rise to economic activities, to new town development, and to the establishment of recreational resorts. Biologists were sure that a severe loss of natural beauty would result.
Apart from these certainties, a number of uncertainties crept into the lengthy discussion. For example, it was unclear how high the total cost of impoldering would be or how the growth of the Dutch population would develop. Other questions arose, for example, whether the water quality in the Ijsselmeer would be affected. Even the supposed certainties became uncertain as it transpired that it might be possible to find ways of keeping some of the threatened bird and fish populations in nature reserves within the new polder. Different interest groups asked the government to apply environmental impact analysis (EIA) to the reclamation of Markerwaard. Although at the time (the second half of the 1970s) the Dutch government had just started to develop EIA regulations, a proper EIA procedure was not followed. The main, official, reason was that the discussions about Markerwaard began at a time when EIA regulations were not foreseen. In fact comparable procedures were followed as many studies were commissioned by the government and other organizations and the decision process was structured around a physical planning procedure in which public participation was one of the main elements. In reality, an important underlying argument for not applying EIA may also have been the fear of the planners that EIA would reveal the many uncertainties associated with the project.
This example shows that uncertainties play an important role in the planning and decision-making processes for major developments. As such projects will shortly come under EIA regulations in the Netherlands, problems of uncertainty cannot be ignored when preparing for the introduction of EIA. Consequently, the Dutch government has paid explicit attention to uncertainty in several research projects as part of its EIA programme in the last three years.