The goal of this paper is to introduce the Spanish legal developments regarding water resources and urban planning over the last few decades. As a consequence of these developments, it is mandatory nowadays that the competent public authorities report on the existence of sufficient water resources to fulfil projected needs from the expected urban developments (new residential areas, industrial zones, etc.).
For decades Spain suffered and unsustainable economic growth based on the building industry and property speculation. That unsustainable economic growth, together with climate change, led to the overexploitation of aquifers and problems of water supply in some geographic areas.
As a result, in 1999 the legislator introduced the need for the competent territorial authority to provide a report on the existence of sufficient water resources during the process of elaboration of the urban plans. Data and information provided by the engineers and other scientists integrated into the State Public Administration are an essential part of those reports.
Ever since, the combination of the will of the legislator – although with a poor legislative technique - and judicial criteria have been gradually reinforcing the requirement for the report, and now it is mandatory and binding
In this research conclusions have been deduced from the analysis of legislation (2001 Water Act, 2008 Soil Act, and Additional Provision 2.4 of the 13/2003 Act), case law (several judgments until 2015 resolving conflicts in several Spanish basins, especially in the Mediterranean area), and legal-scientific doctrine.
Four main conclusions can be drawn from this analysis:
First. Today no urban plan can be lawfully passed in Spain without an official report that ensures the existence of sufficient water resources (i.e. Judgement of the Spanish Supreme Court of 15/07/2015).
Second. Qualified technical staff (scientists, engineers) must participate in the elaboration of those reports together with legal staff.
Third. There is still some reluctance among some operators, public authorities included, to consider that report as binding and mandatory. However, the Spanish Supreme Court has firmly supported the binding and mandatory nature of the report.
Fourth. The joint confluence of several factors is needed to try to prevent violation of the legal protection of the water:
a) Social awareness and education on sustainable development.
b) Public authorities that serve objectively the general interest and provide a high level of technical preparation through highly-skilled engineers and scientists who can transmit that knowledge to other people (e.g. judges) lacking that technical preparation.
c) Independent judicial bodies that take into account the constitutional principle of sustainable development when interpreting and applying the law.
d) The existence of a popular action, so that anyone can access judicial processes.
e) Clear and precise legislation.
An understanding of the Spanish experience, its legislative and judicial evolution and its difficulties may be helpful for other States. In this way, this study is meant to contribute to the balance between urban planning and the rational use of water resources in the context of sustainable development.