The Setúbal Peninsula faces a potential imbalance between water supply and demand in the near future, warns a study promoted by Águas de Portugal, highlighting water reuse and water efficiency as priority solutions.
The study “Setúbal Peninsula – Water Resilience”, presented today in Setúbal by Águas de Portugal and the Setúbal City Council to mark National Water Day, results from a collaborative process that brought together municipalities, public entities, water services managers, the scientific community, and users.
The objective identified for the preparation of the document is the creation of a solid knowledge base to support future decisions in an area undergoing pronounced economic and territorial transformation with the expansion of industrial, urban, touristic and logistic activities, as well as the prospect of the installation of new flagship projects, including the new airport and airport city, the third crossing of the Tagus (Barreiro–Chelas) and the expansion of the South Tagus Metro to Alcochete.
According to the study, the groundwater system of the Tagus-Sado Left Margin Basin is the most relevant underground water mass in Portugal in terms of water availability and the main water reserve of the Setúbal Peninsula, “a territory that depends almost exclusively on groundwater withdrawals for public supply and economic activities”.
“The study presented here warns of a potential imbalance between water supply and demand in the Setúbal Peninsula in the near future that can be avoided through the implementation of structural measures in the short and medium term,” reads the document.
From a technical and environmental point of view, the study adds, there are warning signs that justify an immediate look: “recent studies point to stability or decline in piezometric levels, with greater intensity in drought periods, and to an unfavorable evolution of water quality at the shallower levels”.
On the other hand, it adds, there are significant groundwater extraction hubs near industrial and urban agglomerations, associated with notable drawdowns and signs of saline intrusion in areas close to the coast, and future climatic scenarios point to a progressive reduction in precipitation and, consequently, in annual runoff, with a negative impact on aquifer recharge.
In light of this scenario, the promotion of water reuse in the Setúbal Peninsula is proposed as a priority measure, as a starting point to strengthen the water supply and protect the aquifer system, in parallel with the reinforcement of water efficiency.
“Considering that the industrial sector represents a significant share – and with a growing trend – of the pressure on water resources, it is proposed to develop collaborative and innovative models that promote symbioses between the decentralized systems of industrial units in the territory and the centralized systems of public sanitation services and the production of reclaimed water (water for reuse),” the study states.
In this context, the study points out that the objective will be to mobilize the region’s existing potential, estimated at around 60 hm3, arising from the combination of urban and industrial effluents, promoting their integrated use, in coordination with the adoption of water efficiency measures.
The Setúbal Peninsula is composed of nine municipalities (Almada, Barreiro, Seixal, Sesimbra, Moita, Alcochete, Montijo, Palmela and Setúbal) with nearly one million inhabitants and has a territorial diversity that combines densely populated and industrialized urban areas with extensive natural areas of high ecological value.
According to the study, there are currently 185 intakes for urban supply in the Setúbal Peninsula (ERSAR, 2025) and their distribution across the territory is not uniform, and the licensing of new intakes is subject to strict criteria, including automatic reporting of volumes, installation of level sensors and periodic review of existing licenses.
