water shortage

Water scarcity is the lack of sufficient available water resources to meet the demands of water usage within a region. It currently affects around 2.8 billion people around the world, on all continents, at least one month out of every year and more than 1.2 billion people lack the access to clean drinking water.[1] Water scarcity can be a result of two mechanisms: physical (absolute) water scarcity and economic water scarcity, where physical water scarcity is a result of inadequate natural water resources to supply a region's demand, and economic water scarcity is a result of poor management of the sufficient available water resources. According to the United Nations Development Programme, the latter is found more often to be the cause of countries or regions experiencing water scarcity, as most countries or regions have enough water to meet household, industrial, agricultural, and environmental needs.[2]
Water scarcity involves water stress, water shortage or deficits, and water crisis. While the concept of water stress is relatively new, it is the difficulty of obtaining sources of fresh water for use during a period of time and results in further depletion and deterioration of available water resources.[3] Water shortages may be caused by climate change, such as altered weather patterns including droughts or floods, increased pollution, and increased human demand and overuse of water.[4] A water crisis is a situation where the available potable, unpolluted water within a region is less than that region's demand.[5] Water scarcity is being driven by two converging phenomena: growing freshwater use and depletion of usable freshwater