Infrastructure is planned with certain design life, and it is expected that the infrastructures can be useful during the design life and sustainable.
However, in reality in the field, many infrastructures show unsatisfactory performance due to several factors, both technical and non-technical factors. For example, many urban drainage networks cannot function properly in conveying surface run-off because they are full of waste.
Also, urban drainage networks cannot accommodate surface runoff that occurs due to extreme rainfall that has never been predicted before; or broken road because vehicles traveling through the road carry loads beyond the maximum planned and permitted load limits.
In addition, extreme weather events due to climate change will likely increase disruption to infrastructures. When infrastructures performance in a region is disrupted, it will impact on other sectors, including economic and public health sectors. For example, when the drainage network cannot accommodate surface runoff due to extreme rainfall, there will be a flood disaster that will disrupt economic activity and cause many diseases (water borne diseases).
Fundamentally, infrastructure is built with the aim to provide convenience and to improve the community welfare.
Global warming is defined as the rise of global temperature. The average global temperature of land and ocean has increased during the last three decades and likely continues to increase. The increase in temperature has caused changes in rainfall and atmospheric moisture, which increase evaporation and water vapor. This condition causes more intense rainfall, more storm, and sea level rise.
Furthermore, the average rate of sea level rise in recent decades has been faster than the average rate in the last thousands years. Additionally, vital infrastructures for energy supply, water supply, and transportation system are likely affected by climate change. Extreme weather and sea level rise create new risks to the infrastructures.
Transportation system is essential to ensure the efficient distribution of food, energy, and trade, as well as to facilitate workers and consumers in accessing jobs and markets. In addition, to ensure the electricity provision of a region, energy production and distribution facilities must function appropriately.
The physical damage to these infrastructure systems and disruption of the services due to climate change will cause significant economic and human losses.
Extreme weathers lead to flooding will also weaken the structural support of bridges, increase sedimentation rate in water infrastructure, and increase the risk of landslide or avalanche. Flooding also causes damage to significant freight routes, deteriorate energy infrastructure, and cut the electricity off.
In addition, flooding can also destruct the water supply network and wastewater system. Public facilities, such as hospitals, schools, shopping malls and offices, can also be damaged by flooding.
Climate change brings various impacts to water resources and its infrastructure. Extreme weathers lead to flooding and drought that influence the performance of water infrastructure, such as domestic water supply network, wastewater system, irrigation system, and hydroelectric or micro-hydro system.
The New Climate Economy report of 2016 estimated that worldwide investments in infrastructure would need to increase from $3.4 trillion per year currently to about $6 trillion per year by 2030.
During flooding, the water supply system might be contaminated by pollutant and this condition could be disastrous for human health. During drought, the performance of irrigation system and hydroelectric or micro-hydro system will be disrupted due to insufficient water availability.
Reliable and efficient infrastructure underpins sustainable economic and social development. However, events associated with climate change, such as droughts and floods, affect the provision of infrastructure.
In the past, Kenya has largely reacted rather than being proactive in managing the effects of droughts and floods on infrastructure. This is clearly demonstrated by inadequate level of preparedness experienced before, during and after events of droughts and floods. Further, Kenya is infrastructure-deficit, and large portions of the infrastructure has not developed significantly and is exposed to major risks that emanate from natural disasters.
When droughts and floods happen, they expose infrastructure to more risks of structural damage, wearing out and aging quickly, and thus increasing maintenance costs.
Infrastructure vulnerability to drought and floods is currently a cause for concern in Kenya. This is especially because Kenya is increasingly receiving frequent floods and droughts that have intensified over the last few years, often leading to high incidents of infrastructure failure and thus socio-economic losses.
The analysis of effects of droughts and floods demonstrates that infrastructure is not able to withstand and respond well to the shocks of droughts and floods. It is estimated that the larger the area affected by drought and floods, the greater the infrastructure damage and thus leading to disruption of transport services, increase in operational, maintenance and emergency repair costs.
The New Climate Economy report of 2016 estimated that worldwide investments in infrastructure would need to increase from $3.4 trillion per year currently to about $6 trillion per year by 2030. Planning for the impact of droughts and floods on infrastructure is essential in building resilient infrastructure, according to Deloitte Access Economics, 2012.
However, developing countries make little reference to resilience in infrastructure planning and development. There is an implicit assumption that land use planning, building codes and standards provide adequate requirements for building robust infrastructure.
Resilient infrastructure can withstand the shocks of extreme climate events, thus ensuring continuance provision of adequate and reliable infrastructure services and ultimately reducing the time and costs spent on repairs and maintenance of infrastructure.
As noted by World Road Association, climate variability impacts on the planning, design, construction and maintenance of infrastructure, and therefore effective and targeted actions should be taken towards building resilient infrastructure to minimize the disruption, damage and cost of repair and maintenance
Adaptation actions are required to diminish the impacts of climate change on the infrastructures. Adaptation to climate change will not eliminate all adverse impacts of climate change to infrastructures. However, they can have positive effect on the economic sectors and conducive environment for investment.
According to a study conducted by World Bank as reported by the UK government, the net cost for infrastructures adaptation to climate change is only one to two per cent of total cost of infrastructure provision. In addition, this cost is insignificant in compared with other factors, which may influence the future costs of infrastructures.
