When an individual is water-stressed, it implies that there is no sufficient access to potable water. An estimated 1.1 billion people are under water stress. In countries such as Africa, a large percentage of individuals have no easy access to fresh water. One of the most common methods of acquiring freshwater is by digging holes in riverbeds.  Scarcity of water can also cause water pollution. For instance, if inadequate water is available for sanitation, water gets polluted through the introduction of disease-causing pathogens. In fact, 88% of all water-borne diseases are caused this way.