Congestion, travel cost recreational demand models, and benefit evaluation

The treatment of congestion in travel cost demand models for recreational sites is a subject of considerable importance for both the allocation and management of public lands. In a recent issue of this journal Wetzel argued that the use of the travel cost method will always lead to underestimates of the true benefits provided by a site because of the role of congestion. The purpose of this paper is to show that his results are misleading. It is not possible to derive a priori the direction of the bias in the aggregate demand for a recreational site's services due to congestion in a given season. Thus, Wetzel's conclusions on the bias in benefits are misleading. The most appropriate treatment of congestion requires that travel cost models be amended to reflect the effects of congestion on: (a) the modeling of individual behavior; (b) the estimation of an individual's demand for a recreational site's service; and (c) the description of how a site's services are allocated across individual users.