Learning from hydrological and hydrogeological problems in civil engineering. Study of reservoirs in Andalusia, Spain

Abstract

This study presents a novel review of seven case histories of Andalusian reservoirs (Southern Spain) affected by different hydrological and hydrogeological problems that have led to severe malfunctions. The failures reported are related to (i) water quality degradation due to salinization and acid mine drainage, (ii) leakage in karstified terrains, (iii) environmental and hydrogeological impacts associated with an inadequate water planning and (iv) large evaporative losses from the reservoir. Detailed information on the geological context, hydrological/hydrogeological origin of the problem, repercussions on infrastructure functioning and remedial measures applied or proposed has been gathered for each case. Results of on-site research carried out by the authors in some of the locations studied and a comparative analysis of similar case histories at international level are also included. The purpose of this work is to emphasize the need of learning from past mistakes and provide guidance for future dam construction works, especially in the Mediterranean region. It also highlights the role of geological and hydrogeological research in dam sitting and the consequences of inadequate terrain characterisation, biased hydrological planning and data misinterpretation or undervaluation. This review evidences the need of conducting comprehensive studies that do not only focus on the infrastructure itself, but also on non-constructive aspects (monitoring of geological features and hydrological variables) and relevant processes (e.g. leakage, salinization and contamination) that might compromise the efficient functioning of the infrastructure