In natural systems, floods play an important role in ecosystem functioning, such as by recharging groundwater systems, filling wetlands, and the promotion of breeding, migration, and dispersal of numerous species¹. In natural ecosystems, there is a lot of resiliency to the majority of flood events.
In contrast, in areas that have been developed by humans where the natural resiliency of ecosystems has been lost, floods can be very destructive. They can destroy homes and other infrastructure, and can lead to a loss of crops, to the spread of waterborne diseases, and to a loss of human life. Floods can also disrupt industry, water supplies, wastewater treatment, transport, education, and healthcare, essentially forcing many local economic activities to be halted until rebuilding has occurred¹.
While there are naturally caused floods that would have occurred from time to time that natural systems could mostly handle, our development of a lot of the world’s landscape and our consumptive lifestyles have led to an increase in floods.
The following is a list of some of the human causes of floods.
- Infrastructure failures
- Development and infrastructure in flood-prone areas
- Impermeable surfaces
- Bridge constriction
- Flood embankments
- Climate change
As melting of the the world’s glaciers occurs due to warmer global temperatures, sea level rise is occurring around the world, also leading to an increased risk of flooding in low-lying coastal regions and in heavily urbanized floodplains such as the Nile, Mississippi, and the Ganges-Brahmaptura. Such flooding risks are predicted to increase if greenhouse gas emissions continue unabated.
Some ways that we can prevent flooding
While we as humans have certainly altered much of the natural landscape of the planet, leading to an increase of floods, we can also help to reduce the risks of flooding.
- By restoring natural ecosystems, such as wetlands and coastal ecosystems such as Mangrove forests, we will restore some of nature’s capacity to deal with flood events.
- By planting trees and reforesting areas that have been deforested, we can restore the landscape’s ability to take up and store precipitation. We can also restrict the development of infrastructure within flood-prone areas, such as next to rivers and coasts.
- By moving forward with a sustainable future where only clean energy is used, and by working with Nature’s limits in our own daily lives, we can ultimately help to reduce the risk of flooding as greenhouse gases are reduced and we strive to turn the tide of a warming planet.
- We can plant trees in urban areas and intentionally develop parks and reserves for natural ecosystems that retain the ability to take up rainwater and other precipitation.
- When we engage in development, our development must incorporate permeable surfaces that allow water to recharge groundwater supplies, instead of simply allowing precipitation to runoff and flood vulnerable areas.