The case study describes the calculation of the loss of values of an important wetland area in Hungary using the method of benefit transfer. The Szigetköz wetland is situated at the North-Western part of Hungary on the side of the River Danube. The construction of a barrage system between Hungary and Slovakia, and especially the diversion of water from the main riverbank, caused considerable damage to the valuable ecosystem of the Szigetköz wetland.
An Austrian contingent valuation study was used as a basis for the benefit transfer. The Austrian survey calculated the willingness to pay (WTP) for a wetland (similar to Szigetköz) as an area for a future national park, with and without a hydroelectric power station. The findings were adjusted to the Hungarian case, taking the differences of the two situations into account (e.g. the GDP of the two countries, the territory of the wetland area, and the estimated rate of degradation). The NPV (net present value) of the loss of value using the discount rate of 2% and 3.5% was calculated. As a result, the value of the loss is between 42-252 billion HUF at 2% discount rate and 24-144 billion HUF at 3.5% discount rate. The findings of the benefit transfer were used in cost-benefit analyses of different possible alternatives of the Gabcikovo-Nagymaros barrage system. It is a step toward a much broader economic analysis, including the estimation of the natural capital invested. The results showed that, although Hungary’s investment into the project was of a smaller scale in terms of material assets, a rather significant part of its natural capital has been invested. Due to the known deficiencies of the benefit transfer method, the results might be tested with an original WTP survey.