Climate change presents novel challenges for water management, both in the context of water excess and scarcity, and it is expected to afflict the world in the coming years. The necessity of strong collaboration between urban water management and spatial planning to facilitate adaptation to climate change has been underlined in the literature. Considering the potential of the legislative context to foster this collaboration, this article examines how the objectives and measures for collaboration are foreseen in a set of legal documents. The article focuses on the Portuguese legal context. As a southern European country, Portugal is situated in one region most susceptible to climate change impacts, including water scarcity and flooding. A systematic document analysis was conducted to examine how collaboration is formally foreseen in a set of legislation, plans, programs, and water management-related contracts. The findings reveal that although plans and programs include recommendations for collaboration, this inclusion is much poorer in regulations where the establishment of the necessary steps remains weak. Contractual arrangements between water sector grantors and concessionaires have shown to be even poorer at fostering such collaboration. Further studies applied to other countries could shed light on this challenge.

  • Legal and climate integration: The study uniquely merges legal analysis with climate adaptation, focusing on how laws can enhance collaboration between urban water and spatial planning.

  • Focus on vulnerable Portugal: It centres on Portugal, a country highly at risk from climate change impacts like water scarcity.

  • Reveals legislative gaps: The research uncovers gaps in laws and contracts that hinder collaboration.

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