Sustainable management of human water consumption: a preliminary case study in North-eastern Portugal

摘要

Portugal is experiencing a drought. Since April, 2005, about 80% of the country, including our study area, has had a severe to extreme drought. Hence, there are a lot of difficulties with regards to the current water needs for human consumption, agriculture, ecosystem, etc. This is a scenario that can repeat itself more often in the future because of the effects of climate change. Proper water management is one of the key issues that can make sustainability practical. We studied and utilized a multi-dimensional model in order to capture the dynamics of water use in Portugal. To begin with, we used a municipality in the North-eastern part of the country called Braganca. Although it is more humid than the southern municipalities, nonetheless, it has had severe water problems this year. We used four different dimensions to understand the sustainability of the water supply system of the municipality. These are: price, quantity of the water used, quality of the water used, and the mode of life. Their values were in binomial form: price (free / pay, as some part of the system operated free of charge), quantity of water (low / high, a threshold was defined to separate the two levels), quality of water (satisfactory / unsatisfactory, as related to the legal norms), and mode of life (rural / urban, a crude first step characterization of this social parameter). The results show that the worst scenario reflects the following situation (free, high, unsatisfactory, rural). And the best is (pay, low, satisfactory, urban). This preliminary study has made the authorities of the municipality more aware of the problems of the system and a number of them are being solved. However, to make the model more useful towards a sustainable management, its further refinement is underway, to be also applied to other regions.