Borde costero

In Chilean law borde costero (lit. "coastal border") is defined as; "the said strip of territory that include the public land, the playas, the bays, gulfs, straits and interior channels, and the territorial sea of the republic, [which] makes up a geographic and physical unit of special importance for the integral and harmonic development of the country." The land area within the highest tide, or annual lake level high, and up to 80 m inland from this level is known as the playa (lit. "beach") of borde costero. The concept of the playa is based on article 594 of the Chilean Civil Code and this condition is independent of the actual ground type.

The decree formally defining borde costero and many of its regulations was issued in December 1994. Its scope is based on an interpretation of the Chilean Civil Code. Borde costero is considered a sui generis definition without equivalents in legislation outside Chile. The Subsecretariat of the Armed Forces is tasked with granting concessions in borde costero except in rivers and lakes that have not been declared navigable for ships over 100 tons where municipal administrations do so.

The Chilean regulations regarding borde costero have been criticized as failing to balance competing land use interests such as port facilities, real estate development, and environmental and landscape conservation, leading to a total dominance of the two former. Regulations are also criticized for lacking citizen participation mechanisms. The coast of Valparaíso Region in particular has been the site of socio-environmental conflicts, and environmental and landscape degradation attributed to real estate development allowed by the borde costero regulations. Various coastal wetlands and dunes in Valparaíso Region have been urbanized since 1994, for example, those in the area between Concón and Reñaca.

In May 2023 the National Commission on the Use of Borde Costero announced that the concept of borde costero will be replaced for that of zona costera. Reportedly the change has been made to widen the geographical scope of regulations beyond beaches and 80 m inland from the highest tide.