One of the most notable changes in modern times is the rapid urbanization of our planet, which began in the 19th century. While in 1950, 29 percent of the global population lived in cities, that figure is estimated now at around 50 percent, and by 2030 it will reach 61 percent.
It is estimated that, by 2030, 61 percent of the population on that continent will be living in cities. Not only are more people living in cities but the cities themselves are becoming larger and more densely populated. This situation poses unique problems related to the provision of water, sanitation, and a healthy environment.
Since 1990, the number of cities in Africa has increased from 3 000 to 7 600, and their population has increased by 500 million people. Africa has now 19 cities with populations of more than 1 million inhabitants. Because of slow economic growth, lack of effective development policies, and limited resources, the development of infrastructure has not kept up with the increasing needs for shelter and services in growing urban populations.
This is the case for many African cities, where local governments have been unable to keep pace with change and, as a consequence, have been unable to provide dwellers with proper infrastructure related to the provision of potable water and the collection, transportation, processing, and disposal of waste materials.
In addition to the problems caused by insufficient lack of potable water, in developing countries with economies under stress, waste management is a problem that often endangers health and the environment. This situation is given low priority by governments often besieged by other problems such as poverty, hunger, children’s malnutrition, unemployment, and war.
Poor hygiene, inadequate management of liquid or solid waste, and lack of sanitation facilities are contributing factors in the death of millions of people in the developing world due to diseases that are easily preventable. In addition, people living in un-serviced or poorly serviced areas value the increased convenience and privacy associated with improved sanitation.
Lack of sanitation and inadequate disposal or storage of waste near houses can provide habitats for vectors responsible for several infectious diseases such as amebiasis, typhoid fever, and diarrhea. Uncontrolled and inadequate landfills are a danger to the environment and a health risk to the population since they may lead to contamination of water and soil. The health risks associated with poor sanitation tend to be higher in densely populated low-income urban areas. At a global level, more than 5 million people die each year from diseases related to inadequate waste disposal systems.
Contamination of water leads to a whole range of diarrheal diseases, such as cholera, that kill 1.8 million people annually worldwide. An estimated 90 percent among them are children below 5, mainly from developing countries. Most of the burden can be attributed to unsafe drinking water, inadequate sanitation, and poor hygiene practices.
The children that are affected the most are those living in low-income urban areas. According to UNICEF, infant mortality rates (IMRs) are almost always higher in poor urban areas than the national average and than those in rural areas. A great proportion of the high mortality among the children of the urban poor can be attributed to diseases common in urban areas such as diarrhea, tuberculosis, and parasitic diseases (intestinal worms) that are frequently associated with lack of safe water and sanitation. Malnutrition in children is often a consequence and a complicating factor.
Microbes, particularly those present in water, food, or on dirty hands are the most frequent cause of sickness worldwide. Although lack of safe water and sanitary facilities are significant problems, they are made even worse by ignorance in the general population, particularly mothers, about the connection between dirt, microbes, and childhood diarrhea.
Several naturally occurring and human-made chemical substances present in drinking water can have a serious effect on health, particularly in high concentrations. Among chemicals that can be dangerous at elevated levels are fluoride, arsenic, lead, cadmium, mercury, nitrates, and pesticides.
All these factors stress the need to implement policies that ensure the provision of safe water to the population, particularly in marginal areas lacking basic health and social services.
Africa has the lowest water supply and sanitation coverage of any region in the world. It is estimated that one in three Africans has no access to improved water or to sanitation facilities and the number of people lacking those basic services is increasing. The majority of those lacking basic services live in informal or suburban areas and rural communities.
It is necessary to overcome the lack of integration between the various components of environmental sanitation: excreta, domestic and industrial wastewater, solid waste, and storm water, which are often run by separate agencies or institutions. Better use of synergies can lead to more sustainable and cost-effective solutions.
Dr. César Chelala is an international public health consultant and a winner of an Overseas Press Club of America award and two national journalism awards from Argentina.