- Old vehicles emit hydrocarbons and smoke to the atmosphere at up to five times the rate of emissions from new vehicles.
- The situation is expected to deteriorate in the years to come as official data shows that Kenya imports an average of 7,600 vehicles per month.
Urban mobility is rapidly becoming one of the greatest challenges facing both developed and developing countries alike.
Nairobi is often listed among the most congested cities in the world. The Nairobi Metropolitan Area Transport Authority has ranked Nairobi as the world’s fourth most congested city with average travel time in the city at 57 minutes.
The situation is expected to deteriorate in the years to come as official data shows that Kenya imports an average of 7,600 vehicles per month.
Compared to other urban centres in Kenya, Nairobi has the greatest concentration of vehicle air pollutant sources.
This is partly due to the fact that most of the imported second-hand vehicles are used mainly in Nairobi.
Nairobi’s transport infrastructure is ill-equipped to handle the additional travel generated by the increasing population. The transportation sector is increasingly being recognized as the highest polluter, emitting atmospheric harmful gases and other toxic chemicals.
Old vehicles emit hydrocarbons and smoke to the atmosphere at up to five times the rate of emissions from new vehicles.
In 2016 for instance, Kenya’s air contained double the recommended volume of particulate matter (the term for a mixture of solid particles and liquid droplets found in the air) for outdoor air pollution. Around 40 per cent of CO₂ emissions were attributed to the transport sector.
Pollution can have a negative effect on the marginalised and the vulnerable due to their general health status, potential higher exposures and reduced resilience to social, environmental and economic risks.
In particular, air pollution is the world’s single greatest environmental risk to one’s health. Air pollution is associated with respiratory and eye diseases such as asthma, lung cancer and conjunctivitis, especially in children and the elderly.
People who spend substantial time on or near roadways, particularly motorists, pedestrians, traffic police and those engaged in the many informal businesses located along roadways, are also of particular concern regarding potential human health impacts.
United Nation Environment Programme (UNEP) has in many occasions highlighted that motor vehicle emissions have well-known health effects which may be exhibited with short term exposure, including wheezing, coughing, shortness of breath and sore throats as well as irritation of existing respiratory conditions such as asthma.
According to the Kenya National Bureau of Statistics, pneumonia has recently been the top killer disease, dislodging malaria, from 2015 to date.
In addition, respiratory system ailments are the most common diseases in local health facilities.
Studies show there is a connection between air pollution and respiratory diseases. Air pollution has been shown to exacerbate respiratory diseases and also increase the risk of pneumonia.
The COVID-19 pandemic has cast a spotlight on the risks to human health posed by air pollution.
Though scientists are investigating possible links between exposure to air pollution and susceptibility to the COVID-19 virus, it has been established that air pollution harms human health in myriad ways.
Air pollution is a risk factor for certain illnesses, such as respiratory and cardiovascular diseases - these same diseases put people at a higher risk from COVID-19.
Without immediate investment in urban transport infrastructure and services, the average trip speed to work will continue to decline and consequently the health of our people. Modernization of Nairobi’s road infrastructure will be pivotal to reducing emissions and volumes of traffic.
One of the projects that could have a significant impact on air quality in the city is the Nairobi Expressway which is designed to start from Mlolongo all the way to James Gichuru junction.
It is expected to eventually reduce the travel time through Nairobi from 2 hours to about 20 minutes.
This road, which will have a Rapid Bus Transport component, will also provide a model pilot to improve the public transport services in urban areas, especially the Central Business District and the developed high-density corridor.
A modern and efficient transport sector will ultimately improve the quality of urban life, including addressing social inequities and will mitigate the effects of air pollution on the health of our people.
Mr. Mwaura is a communication consultant with a focus on infrastructure development.