Influence of salt concentration and topographical position on water resource quality: The Spanish Case Study

Abstract

Water resource quality (WRQ) is affected by salt concentration and topographical position. Indeed, an increase in salt concentration,
which decreases water availability for animal and plant nutrition, and lower altitude, which diminishes the potential
for production of hydropower, negatively affects WRQ. Therefore, it is useful to develop indicators like osmotic power (OP)
and hydraulic power (HP) to evaluate, respectively, the influence of salt concentration and topographical position on WRQ.
The main objective of this work was to evaluate the WRQ in 11 hydrographical basins in peninsular Spain. In this paper, OP, HP
and the total power (TP), obtained by adding OP to HP, were calculated at three different basin levels:
• Height H25 (m) corresponding to 25% of total surface area of the basin
• Height H50 (m) corresponding to 50%
• Height H100 (m) corresponding to 100%.
Results showed that OP, HP and TP values of water basins decreased from the northern to the southern parts of peninsular
Spain, according to water scarcity and hydrographical characteristics of water basins. The higher OP, HP and TP values, the
higher is WRQ of the basin. Therefore, TP, OP and HP can be used to evaluate WRQ at the administrative water basin level
as a basis for water resource management. Indeed, these indicators can assist water managers and planners in deciding between
inter-basin water transfers and water desalination, especially in countries where water is a scarce resource.

Water SA Vol.31 (2) 2005: pp.199-208