Author name: Franklin W. Schwartz

Around the world, groundwater sources are in decline due to overpumping and pollution. History informs us that as water supplies are lost so are civilizations. Such was the case with the Garamantian civilization, which thrived in the western Libya desert from 500 BCE to 400 CE, then disappeared when the groundwater ran out. Present-day mining of groundwater from large aquifers in the United States, North Africa, and China illustrates this problem. In less than a century, pressures from food production and population growth are leading to declines in supplies that appeared to many as inexhaustible. In many countries, there can be no replacement for declining water resources. Food scarcity and health epidemics, leading to societal decline, are likely outcomes as people chase dwindling water supplies.

The chemical constituents in water determine its potability, usability for agriculture and recreation, and interactions with biological systems. Anthropogenic processes have significantly influenced the geochemistry of water in many regions. Physical, chemical, and biological processes control the chemistry and chemical evolution of water in natural and contaminated systems. Advances in our ability to quantify these processes will improve our ability to manage our water resources, help us identify potential sources of contamination, and illuminate potential solutions to water-quality problems. Particularly impressive are the applications of chemical and isotopic tracers, which can track water movement and quantify water fluxes on the surface and in the subsurface. To better address societal needs, future advances will require a holistic approach to interpreting geochemical data.