It is human nature to try to control the natural world. Even before history was written, people have tried to control forces of nature, such as rivers. The practice of straightening rivers became popular for some time, but now people are beginning to understand the effects straightening rivers has on the environment.
How many times have you seen a river that was naturally straight? Twists and turns help control the speed of a river's course. Water is a useful and necessary resource. It did not take long for people to take steps to manage rivers in a way to enhance their usefulness. There have been many steps taken to ensure rivers do not interfere with human development.
Rivers have been used for transportation for centuries. From transporting people to goods, rivers were inexpensive transportation. The course of a river affects the speed at which it transports materials. Twists and turns in a river will lengthen a journey. Straightening a river between points A and B will make the river shorter. The river's flow would also increase.
Rivers act as a food source. There are many forms of aquatic life that satisfied the pallet for generations. Many fish traps and other obstacles have found homes in the river to catch these sources of food. Drinking water and water for irrigation are additional uses of water to create food sources. Major cities have developed alongside rivers for these very reasons.
Energy is harvested from rivers. In the 1800s, watermills were developed for production. The power of water has been used in many industries, including the textile industry.
As needs from the river increased, people developed enhancements to improve efficiency. Straightening rivers is just one method of human intervention to manage water's resources and make passage along rivers easier. It has even been used as a method of flood control.
Effects of straightening rivers on the environment are being realized more every day. Straightening rivers leads to a reduction in wetlands. Wetlands are important to rivers because they help keep water levels normal. By absorbing water, they prevent flooding naturally. They release water when levels are low. Wetlands also provide a home for wildlife and provide vegetation to help feed fish in the river.
With shrinking wetlands, there is also a threat of increased flooding. As cities popped up next to rivers, new drainage systems developed. Natural drainage systems were reduced or removed completely. These man-made drainage systems can be overloaded and lead to flooding. Even though straightening a river reduces flooding in one section, it opens up increased flooding downstream.
Straightening rivers modifies their characteristics. This leads to a population decline in fish species. An ancient fish and two shorebirds on the Missouri River have become endangered due to hundreds of years of human intervention. As rivers flow faster, soil erosion occurs more quickly. This affects animal habitats.
When humans first began straightening rivers, the environment was not considered. Today, protecting natural resources and the environment is more important. Steps have been taken to return some rivers to their natural state. Also a call for no reduction in wetlands has been enacted. The effects on the environment must be considered now before changes are made.
"All Along the River" http://library.thinkquest.org/28022/
"Competing visions divide Missouri River fans" http://www.desmoinesregister.com/apps/pbcs.dll/artic le?AID=/20090719/NEWS/907190346
"Infocus: Floods" http://www.pbs.org/newshour/infocus/floods.html