Over the last few decades, flood disasters have become more and more regular not only because of climate change but also owing to urbanization and other related natural factors.
However, the conventional wisdom in infrastructure design exacerbates the damage that many of these floods cause. Most of these techniques employed in infrastructure construction, including the drainage system, expansive and rigid road network, and control of river flow, were not developed bearing in mind the impacts of severe weather conditions.
Such designs, which have been adopted in the past as cutting-edge, are now failing to address emerging climate changes. This has led to the need to redesign the infrastructure as a way of addressing this problem and increasing its resistance to the impacts of severe flooding.
The Problem with Rigid Drainage Systems
For example, one of the major drawbacks of conventional construction is the utilization of the stiff drainage pattern. These systems include stormwater drains, culverts, and sewers, which are aimed at promoting fast drainage of water from the urban setting.
As for the above-said approaches, this method is suitable only for the small to moderate rainfall events but not for the extreme-range ones. Such systems are normally developed based on past rainfalls and therefore cannot accommodate the current and expected changes in climate systems where storms are heavier and more frequent.
However, during an intense flood event, these rigid systems can be overwhelmed, thus causing backflow, obstruction, and flooding in urban areas. Also, conventional drainage systems do not take into account the vegetative infiltration capability of the soil in most cases. Hence, water is channeled and removed from areas that are supposed to receive it, which, with increased concentration and speed, makes flooding downstream worse.
Urbanization and Impermeable Surfaces
Another factor that has actually aggravated situations connected with floods is the increased rates of urbanization observed during the last few decades. The conventional approach for the design of infrastructure involves the creation of non-porous systems, including paved roads, concrete sidewalks, and structures. These surfaces do not allow water to percolate into the ground; this results in higher rates of runoff during instances of precipitation.
This surface runoff is bad, especially in urban areas, because it overloads the drainage systems and causes flash floods. Moreover, these impermeable surfaces affect water resources in that they are able to slow down on the recharging of groundwater.
The Consequences of River Channelization
In the past, there have been so many rivers that have been linearized, and this is normally a regular procedure in infrastructure engineering as it calls for the streamlining of the river to this channel in a bid to facilitate some sort of regulation of the waters.
Although this method was in the past utilized to control flood in specific regions, it has had side effects. The channelization of water bodies such as rivers means that water can be moved at a faster rate hence reinforcing erosion, and there are little or no natural floodplains that will help in accommodating excess water during floods.
In addition, channelization reduces the winding of river channels, which is vital in slowing down the water speed and thus preventing the occurrence of floods. The above considered traditional infrastructural designs aim at eliminating these natural features, consequently worsening the impacts of floods downstream.
In the same context, floodplain erosion and loss resulting from channelization decrease ecosystem resilience, limit spaw of wide range of species, and hinder their capacity to restore after the flood phase of extreme weather.
Moving Toward Resilient Infrastructure Design
With the problems of dealing with such massive floods in the current template of infrastructures, there is a slowly building consensus to embrace a more robust and flexible approach. One response is therefore to integrate the green infrastructure, for instance wetlands, permeable area pavement, and urban forest that aids in absorbing and then slowing the flow of water during the rainfall. What makes such approaches effective are natural systems that stimulate natural functions that can ease the pressure on inflexible drainage systems.
Another measure applied to the generalized construct of resilient infrastructure design is the inclusion of flood planning into the urban design. Some of the measures that have been recommended include foregoing the construction of structures in regions that are prone to floods, creating flood plains that enable rivers to flood safely, and putting in place early warning systems to help communities prepare for floods.
Life is too important to be negligible, and often it does not take much to become a part of the solution but only a small amount of thinking and action In this case, reconstruction of infrastructure can go a long way in preventing devastating floods and establishing communities and societies that would be able to withstand the challenges of climate change.
Conventional bridge design is used in the normal condition of flood and cannot adequately meet the current severe flood condition. There are four such practices, which include rigid drainage systems, urbanization, and river channelization, among others.
Therefore, there is a need to develop better infrastructure practices that will be resistant to climatic changes and more effective methods of flood control that are sustainable in the long run.
ASH CK