Urban planning requires the integration of several disciplines, among them ones related to water resources. The impacts of urban development on those resources, and viceversa, are well known, but some aspects have not been well characterized in literature. This research analyzes a case that shows interesting relationships between urban planning, its legislation, the evolution of urban occupation and several aspects of water resources: groundwater, surface water, drainage and saltwater intrusion. The research argues for integrated and dynamic planning, monitoring and directive enforcement of the urban processes, including environmental dimension and water resources. Advanced decision support techniques are suggested as tools for supporting this integrated approach.