The ‘escalator effect’ in flood policy: the case of the Costa Brava, Catalonia, Spain

Abstract

This paper examines flood policies in the context of ephemeral and low-flow streams of the Costa Brava region of Catalonia, Spain. It argues that these streams are subject to the ‘escalator effect’ whereby hydraulic works expand to protect increasing levels of development in areas exposed to flooding. A survey undertaken with local municipal officials indicates that this continues to be the preferred alternative in flood policy. Environmental values could become a convincing way to break down the ‘escalator effect’ but their force is diminished by the low social appreciation of ephemeral streams.

Introduction

With reference to flood policies in England and Wales, Parker (1995) discussed a very common trend in the relationship between floods and societies, defining it as ‘the escalator effect’. By this he meant the higher standards of structural protection being demanded as material wealth accumulates in flood-prone land and the real or perceived threat of flooding intensifies. The cycle continues as more development occurs after this protection has been provided, thus increasing flood damage potential, and so more protection is requested, and so on.

Parker's conceptual and empirical analysis of the ‘escalator effect’ represents a refinement of the well-known tradition of flood studies in Anglo-American geography developed by Gilbert White and his colleagues (White, 1945, White, 1975). While Parker, in line with White's approach, was concerned with alternative ways of reducing flood damage potential, the present paper explores another aspect of the ‘escalator effect’ – its role in the denaturalization of Mediterranean ephemeral streams. Increasing levels of protection imply a progressive loss of the biophysical characteristics of these streams and their final transformation into human-made channels. This process becomes more acute when beneficial functions (groundwater recharge, soil fertility, species diversity, coastal conservation, etc.) remain hidden from the eyes of policy-makers and the public, or when these streams do not fit into prevailing aesthetic and functional standards of urban quality.

The objective of this paper is to present a case study of the ‘escalator effect’ in the Costa Brava region of Catalonia, Spain, one of the leading European tourist destinations. It has experienced drastic environmental change since the 1970s, largely as a result of urbanization, one of the main environmental impacts being the alteration of the hydrological cycle, exacerbating the natural tendency towards flash floods that characterizes most of the fluvial systems of the region. The response to increasing flood episodes has followed the common path of building flood defence works and, at the other end of the management sequence, providing public relief funds. Despite calls to break the dependence on these two forms of adjustment to floods and to explore other solutions (notably land-use controls), the ‘escalator effect’ appears to persist in this area, and flood control structures maintain their hegemony as the most desired alternative in flood management.

The paper is organized as follows. First, after introducing Mediterranean ephemeral streams in the context of flood management, it sets down some of the constraints for breaking the ‘escalator effect’. Second, the biophysical and socioeconomic reality of the Costa Brava is presented, an area where a fluvial system prone to flash floods coexists with intense urbanization pressures. This is followed by an analysis of a survey undertaken among local managers in the different municipalities of the Costa Brava regarding the feasibility of different forms of adjustment to floods in their towns. Finally, the paper offers some conclusions on the flood problem in the study area.