Water resources

Water resources are sources of water that are useful or potentially useful. Uses of water include agricultural, industrial, household, recreational and environmental activities. Virtually all of these human uses require fresh water. 97% of the water on the Earth is salt water. However, only three percent is fresh water; slightly over two thirds of this is frozen in glaciers and polar ice caps.[1] The remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction present above ground or in the air.[2] Fresh water is a renewable resource, yet the world's supply of clean, fresh water is steadily decreasing.[3][citation needed] Water demand already exceeds supply in many parts of the world[where?][citation needed] and as the world population continues to rise, so too does the water demand. Awareness of the global importance of preserving water for ecosystem services has only recently emerged as, during the 20th century, more than half the worldТs wetlands have been lost along with their valuable environmental services for Water Education.[citation needed] The framework for allocating water resources to water users (where such a framework exists) is known as water rights. Water right in water law refers to the right of a user to use water from a water source, e.g., a river, stream, pond or source of groundwater. In areas with plentiful water and few users, such systems are generally not complicated or contentious. In other areas, especially arid areas where irrigation is practiced, such systems are often the source of conflict, both legal and physical. Some systems treat surface water and ground water in the same manner, while others use different principles for each. Water rights generally emerge from a person's wnership of the land bordering the banks of a watercourse or from a person's actual use of a watercourse. Water rights are conferred and regulated by judge-made Common Law, state and federal legislative bodies, and other government departments. Water rights can also be created by contract, as when one person transfers his water rights to another. In the eighteenth century, regulation of water was primarily governed by custom and practice. As the U.S. population expanded over the next two centuries, however, and the use of water for agrarian and domestic purposes increased, water became viewed as a finite and frequently scarce resource. As a result, laws were passed to establish guidelines for the fair distribution of this resource. Courts began developing common-law doctrines to accommodate landowners who asserted competing claims over a body of water. These doctrines govern three areas: riparian rights, surface water rights, and underground water rights. An owner or possessor of land that abuts a natural stream, river, pond, or lake is called a riparian owner or proprietor. The law gives riparian owners certain rights to water that are incident to possession of the adjacent land. Depending on the jurisdiction in which a watercourse is located, riparian rights generally fall into one of three categories. First, riparian owners may be entitled to the "natural flow" of a watercourse. Under the natural flow doctrine, riparian owners have a right to enjoy the natural condition of a watercourse, undiminished in quantity or quality by other riparian owners. Every riparian owner enjoys this right to the same extent and degree, and each such owner maintains a qualified right to use the water for domestic purposes, such as drinking and bathing.