Water, the intangible element

Water is the key to life. No living creature can survive without water. Too much water or polluted water are serious threats to mankind. Managing this intangible element is complex, not only in wet deltaic regions but also in the (semi-)arid regions of the world. Combined efforts of the hydro(geo)logical, (geo)chemical, (micro)biological and mathematical sciences are essential to find answers to intricate quantitative water management issues. Not only confined to freshwater quantity problems, but also with respect to water quality. In most coastal regions in the world, fresh water is produced in the vicinity of the fresh-saltwater interface. The hydrological processes underlying sea-water intrusion in deltaic and semi-arid regions will be discussed, as well as the mathematical analysis of these processes. In addition attention will be given to the ever decreasing knowledge and skills of Dutch high-school students w.r.t. mathematics and physics. This is a real tragedy, not only for the high-school students, but also for the future of the quantitative sciences in academia. The inaugural lecture concludes with the observation that the Netherlands are facing a serious shortage of academic water managers/hydro(geo)logists. The number of traditional jobs is more or less constant over the years, e.g. water supply companies, water boards, provinces, water and soil research institutes, etc. Due to climate changes and sustainable developments such as geothermal energy, aquifer thermal energy storage, storage of CO2 in the subsurface, the number of job opportunities for quantitative water managers and hydro(geo)logists has enormously increased. If we are not able to interest more young people to start a career in water-related sciences, a serious problem emerges for The Netherlands: more than enough water, but almost no one knows how to deal with it (anymore).