Reservoirs and lakes are used for similar reasons, and can be found in many different locations. Lakes are natural bodies of water than can vary vastly in size. Reservoirs are man-made bodies of water that are created for many different reasons. They can be made for financial gain or simply to preserve the local environment. Both are called ‘standing waters’.
Lakes are standing waters that have formed over many, many years. They occur naturally, as a result of the shifting earth and collections of water beneath the ground. They are useful for a number of reasons. The water in lakes can be purified for drinking water, they benefit the local wild life and they are a crucial element of the beauty of the local landscape.
Reservoirs are similar in nature to lakes, but they are man-made; created to store water or control flooding. Many reservoirs contain water that is to be purified and reused as drinking water, while many are placed in the way of rivers to control the flow of the river and to prevent flooding. They are often placed next to dams, which control the amount of water that passes from the reservoirs.
Standing waters are often very rich in nutrients, and this can be seen by the amount of algae on the surface of the water. These nutrients allow plants and animals to thrive, and create very active environments around the bodies of water.
Reservoirs and lakes that are rich in nutrients and wildlife are called eutrophic standing waters. Reservoirs and lakes often have very fragile ecosystems. The introduction or increase in population of a certain species of fish or plant for example can hugely upset the natural balance of the environment. Pollution is a major cause for concern, and can have a devastating impact on the flora and fauna of these standing waters. When the life found in a reservoir or lake is balanced, the water is well oxygenated and has the right amount of nutrients in it. This means that it is ideal for the many purposes the water is used for.
Upsetting the balance can mean the water has to undergo thorough purification processes before it is usable. Because of this, it is important to maintain a stable environment in reservoirs and lakes. The government has put many measures in place to protect these bodies of water, and to preserve the ecosystems they host.