Abstract
<jats:p>The article examines the territorial, environmental, and economic impacts resulting from institutional disarticulation in coastal management in Mazatlán, Sinaloa. It argues that regulatory fragmentation and weak coordination among government levels have encouraged the construction of rigid infrastructure along the urban coastline, contributing to beach width reduction and the deterioration of its tourism functionality. The research is conducted as a case study with a mixed-methods approach, predominantly quantitative, through a multitemporal geospatial analysis of the coastline from 2005 to 2025. High-resolution satellite imagery, shoreline digitization, temporal overlay in geographic information systems, and validation with georeferenced photographic records were used, along with a review of the current regulatory framework. The results show an average shoreline retreat of -1.2 m/year in urban areas close to infrastructure, as well as a reduction of more than 35% in sandy area available for recreation. Additionally, 27.63% of the coastline shows active retreat. Overall, the findings confirm the relationship between coastal urbanization and the loss of public coastal space, highlighting the need to integrate scientific evidence into sustainable coastal management.</jats:p>