The political economy of coastal development

Coastal development has advantages, such as job creation, and drawbacks, such as the loss of environmental amenities, for both residents and non-residents. Local governments may prioritize their constituents' interests, resulting in suboptimal coastal development. We investigate how political alignment among neighboring mayors facilitates intergovernmental cooperation in the development of coastal areas. We leverage causal effects by applying a close-elections Regression Discontinuity Design to the universe of buildings in Spain. Municipalities with party-aligned mayors develop 46% less land than politically isolated ones, and politically homogeneous coastal areas develop less than fragmented ones. The effect is more salient for land closest to shore or previously occupied by forests, in municipalities with a large share of protected land, and for relevant environmental markers, such as air and bathing water pollution. These results underscore the importance of cooperative political endeavors in managing development spillovers, with environmental considerations assuming a central role.