By Frank Kweronda
In our Kampala City, flooding is often a concern. Floodwaters can quickly cover main roads and highways during storm events, often preventing evacuations, rescues and have in the past and of late caused deaths of our citizens.
It is vitally important for citizens to be well informed and take preventative actions.
Many debate if it is possible to develop a modern economy without properly managing the disaster risks posed by floods. Urban planning should be well adapted to make provision for the increasing number of floods hence the negative effects of these floods on the population and urban infrastructure will eventually be reduced.
On the other hand, despite the efforts to improve drainage system, solid waste still causes blockages resulting in flash flooding and necessitating emergency clearance of the drainage channels. This happens despite the fact that the KCCA is trying to implement an improved citywide solid waste management system. Impacts from flooding are growing and may become much worse in the future.
Schemes must balance the short and long term and integrate structural and non-structural measures in planning.
Flooding is having a major impact on millions of people every year and therefore flood risk management measures need to be implemented in the short term. The impact of urbanization on flood management is currently and will continue to be significant. But it will not be wholly predictable into the future.
In addition, in the present day and into the longer term, even the best flood models and climate predictions result in a large measure of uncertainty. This is because the future climate is dependent on the actions of unpredictable humans on the climate and because the climate is approaching scenarios never before seen.
Urban planning and management which integrates flood risk management is a key requirement, incorporating land use, shelter, infrastructure and services. The rapid expansion of urban built up areas in Kampala also provides an opportunity to develop new settlements that incorporate integrated flood management from the outset.
Adequate operations and maintenance of flood management assets is also an urban management issue. Some of the measures to reduce on the flood risk may include:
Short-term: Improve the drainage systems in our city and also get rid of polythene bags (Kavera) that make it difficult for water to percolate through the soil hence increasing the surface runoff. Do not attempt to drive through standing water or walk through flooded areas. It's easy to lose your balance.
Medium to Long Term: Upgrade the standards of construction for roads, particularly city roads that serve as a lifeline during the flood period, with proper levels and provision of drainage structures. These standards should be made mandatory for all roads constructed in future. A survey initially may be carried out to identify roads lacking these standards.
A systematic program then could be adopted to upgrade these structures instead of restoring in a piece-meal fashion year after year after each flood. This would help reduce the damages considerably and save lives. Roads should also be made multipurpose, where possible.
Invest in protection of major towns where population density and property values are high. Beginning with manageable investments perhaps. Structural measures, including drainage systems, flood protection walls and dykes, together with the construction of bridges for flooded settlements, are important components of the city’s flood protection strategy. These are complemented by measures improving both flood prevention and management of flood hazards. These approaches include management of traffic and the provision of pumping deployments.
Understanding the type, source and probability of flooding, the exposed assets and their vulnerability are all essential if the appropriate urban flood risk management measures are to be identified.
The suitability of measures to context and conditions is crucial: a flood barrier in the wrong place can make flooding worse by stopping rainfall from draining into the channel or by pushing water to more vulnerable areas downstream, and early warning systems can only have limited impact on reducing the risk from flash flooding.
Successful long term implementation of flood risk management measures requires clear leadership, strong champions and the right institutional and legislative frameworks. It is critically important to monitor and benchmark flood risk management even when there has not been a flood event for some time.
Awareness-raising measures should be implemented to increase the local population’s knowledge of the potential dangers of extreme weather events that cause flooding, and the measures should be taken at household and community levels to adapt to them.
Ongoing communication counters the tendency of people to forget about flood risk. Even a major disaster has a half-life of memory of less than two generations; and other more immediate threats often seem more urgent. Less severe events can be forgotten in less than three years.
Flood risk management therefore needs champions at the city, regional and national level in order for it to be brought to the table, as appropriate, in major developmental decision making processes. Issues with a strong champion in a position of influence tend to be more successfully addressed in general.
Having the vision for integrated flood risk management in place in advance of when circumstances for change are favorable can be a factor in successfully exploiting any such opportunity as it arises.
The writer is a civil engineer