DISCOVER
×

Positive Effects of Floods

Updated April 17, 2017

People have come to regard floods as disasters. Humans have altered the flow of natural waterways to meet their needs, with sometimes disastrous consequences. Though floods can be devastating to population centres, they have always been an integral part of nature's renewal process, providing many long-term positive effects.

Renewal of Groundwater and Wetlands

Floods contribute to the health of ecologically important wetland areas. Healthy wetlands promote healthy water supplies and even affect air quality. Floods inundate wetlands with fresh waste. They also carry and deposit nutrient-rich sediments that support both plant and animal life in wetlands. Flooding also adds nutrients to lakes and streams that help support healthy fisheries.

Returning Nutrients to Soil

Floods distribute and deposit river sediments over large areas of land. These river sediments replenish nutrients in topsoil and make agricultural lands more fertile. The populations of many ancient civilisations concentrated along the floodplains of rivers such as the Nile, the Tigris and the Yellow because periodic flooding resulted in fertile, productive farmland. The construction of the Aswan High Dam prevented the Nile from flooding major population centres downriver, but it also depleted once fertile agricultural lands along the banks of the river.

Preventing Erosion and Maintaining Land Mass Elevation

Soil deposited by floodwaters prevents erosion and helps maintain the elevation of land masses above sea level. The rapidly receding land of the Mississippi River delta is a direct result of man-made flood controls and levees that prevent topsoil-replenishing sediments from being deposited in the delta.

Recharge/Replenish Ground Water

Many population centres depend upon groundwater and underground aquifers for fresh water. Floodwaters absorb into the ground and percolate down through the rock to recharge these underground aquifers which supply natural springs, wells, rivers and lakes with fresh water.

Cite this Article A tool to create a citation to reference this article Cite this Article

About the Author

Doug Donald has been writing online since 2004, covering business, relationships, health/exercise and food. His work has also been featured in the "Grosse Pointe News," magazines and corporate newsletters. Donald holds a Bachelor of Science in business and economics, as well as a Master of Business Administration from Central Michigan University.