Every year, Lusaka experiences flooding that causes significant damage to infrastructure and poses a threat to public health. While there are a number of factors that contribute to this problem, one of the key drivers is the city's water table, which is located relatively close to the surface and can easily become overwhelmed during periods of heavy rainfall.
In this blog post, we'll take a closer look at the Lusaka water table and explore the reasons why the city is so vulnerable to flooding.
First, it's important to understand that Lusaka is situated along a gradual slop as water flows toward Kafue river. Another factor contributing to the problem is the fact that Lusaka's water table is located relatively close to the surface, in some areas as little as one meter down. This means that even relatively small amounts of rainfall can cause the water table to become saturated, leading to flooding in low-lying areas.
In addition, the rapid pace of urban development in recent years has disrupted many of the natural water systems that once helped to regulate the flow of water in and around the city.
One of the key effects of this disruption has been a reduction in the amount of water that is able to seep into the ground; because of so much cement, tar and paving on the ground; where it can be stored in the water table and used for things like drinking water and irrigation. Instead, much of the rainwater that falls on the city's urbanized areas simply runs off into the streets and eventually into the city's drainage systems, where it can overwhelm existing infrastructure and lead to flooding.
The situation is further complicated by the fact that many of Lusaka's waterways have been heavily encroached upon by development, especially within the CBD, reducing their capacity to handle excess water during periods of heavy rain. Although many urban road have large open concrete drains along side them, these have proved to be ineffective in moving the water too.
Finally, it is worth noting that climate change may also be a contributing factor to the flooding, as changing rainfall patterns can lead to increased water flow. Instead of a prolonged rainy season with moderate rain, we are now seeing shorter periods of intense rainfall, resulting in flooding.
Overall, the Lusaka water table is a complex and dynamic system that is influenced by a variety of factors, including both natural and human-induced changes to the environment.
While there is no easy solution to the problem of flooding in Lusaka, there are steps that can be taken to mitigate the effects of heavy rain and reduce the risks to public health and infrastructure.