Malaria is one of the leading causes of death in the world. The World Health Organisation (WHO) estimates 300-500 million cases of malaria with over one million deaths each year worldwide. Most malaria cases and deaths occur in sub-Saharan Africa. However, Asia, latin America, and to a lesser extent the Middle East and parts of Europe are also affected. In India, the maximum people affected by malaria are from Odisha State.
The World Malaria Day, instituted by the WHO in 2007, is celebrated on April 25. The say’s campaign theme for 2014 is Invest in the future. Defeat malaria. The day is an occasion to highlight the need for continued investment and sustained political commitment to control and eliminate this deadly disease.
Malaria is transmitted exclusively through the bites of anopheles mosquitoes, which mainly breed in stagnant waters. Some mosquitoes breed in small water pockets partially or completely exposed to the sun while others breed in shaded stagnant water. Malaria transmission is more intense in places where the mosquito lifespan is longer (so that the parasite has time to complete its development inside the mosquito). In many places, transmission is seasonal with the peak during and just after the rainy season. lack of maintenance of the road drainage ditches, drainage water treatment and disposal facilities create problems of silting, slow water flow or stagnant water.
If there are severe storms and excessive rainfall amounts for several days, the ground might not be able to absorb all the water. This leads to development of stagnant water bodies. Another common cause of stagnant water is if the septic systems are filled with too much water, causing the sewage to flow on ground. These types of water are filled with bacteria, creating possible diseases. Areas with a shallow water table are more susceptible to groundwater stagnation due to the lower availability of natural soil drainage. Excessive watering may cause ground or surface water stagnation. People should clean their surrounding environment to clear off stagnant water. During the off flooding period the stagnant water is to be drained off to the nearby water channels. Proper surface and subsurface drainage to remove excess water in a timely manner plays an important role in controlling water-related diseases.
Management of drainage system is presently a challenge for urban authorities in many developing cities because of rapid growth of population and unplanned development activities. Therefore, a close coordination among urban authorities and collaboration between public and private sectors is needed for effective management and sustainable operation of urban drainage system. High-intensity rains can cause urban flooding since urban areas have a lot of concrete structures and there isn’t much open soil available for water to percolate, causing a huge burden on the drainage systems. Several days of flooding allows mosquito larvae breeding and leads to an increase in malaria transmission. Emphasis on drainage development works will have to be undertaken in the severely waterlogged areas to reduce the spreading of diseases.
Floods and waterlogging in the low-lying areas have become common due to unplanned growth. Bhubaneswar’s rapid expansion in all directions makes the city prone to urban flooding. The high rate of urbanisation has led to waterlogging in several areas of the city. It is very crucial to take decisiond while changing land use from agriculture category to residential area. However, as real estate developers and new settlers have started converting agricultural land into residential colonies, the natural channels for water discharge have been blocked.
In Bhubaneswar, the land use change from vegetation to other category was 63.3 per cent and land use change from agriculture to other category was 32.4 per cent in 2000-2005 for residential area which was the highest compared to other category of land uses. This trend is also continuing now. In many cases, people are constructing houses without considering the drainage pattern and they suffer the problem after construction of the buildings. It is very difficult to incorporate drainage plan after construction. In many low-lying areas of Bhubaneswar like Acharya Vihar, Jayadev Vihar, Bhimatangi, Old Town, Jagamohan Nagar, laxmisagar and Kapilprasad, people are suffering from water stagnation. In many cases, construction over the natural drainage channel blocks the water flow.
Common drainage problems can be avoided if due consideration is given to these issues during planning stage. The time and costs spent trying to address problems before and during the construction stage will normally be less than the costs of mitigating efforts after the works have been completed.
Water collected through a road drainage system needs to be carefully discharged from the road, avoiding any damages to the adjacent low-lying land. Equally, the drainage system of a road needs to be carefully adjusted so it does not conflict with the drainage systems on adjacent neighbourhood land. Besides the proper design of side drains can reduce the drainage problem in the city. The function of the side drains (or ditches) is to collect water from the carriageway and surrounding areas and lead it to an exit point where it can be safely discharged. The absence of side drain also aggravates the problem. The exact dimensions of the side drains are dependent on the expected amount of rainwater and the distance to the next exit point where the water can be diverted from the road. The drainage facilities demand management of drains, which involve the prevention of flooding and illegal encroachments, periodic maintenance and provisions of adequate land for future reconstruction and augmentation activities.
Inadequate provision for drainage can increase the risk of malaria. Almost one-tenth of the global disease burden could be prevented by improving water supply, sanitation, hygiene and management of water resources. Such improvements reduce child mortality and improve health in a sustainable way.Malaria can create a huge economic burden for a country. This is due to the number of hospital admissions and the cost of national malaria control programmes. In this context, innovative financing would play an important role. Investments in malaria prevention have been among the best investments in global health facility, resulting in a dramatic decrease in malarial deaths and illness.
Finally, urban planning which is done keeping community needs in mind would go a long way in checking the spread of malaria by participatory planning for better preparedness for potential urban water supply, proper waste disposal and elimination of stagnant water bodies.There is a need to improve waste water treatment, management and modifications to the drainage system in every city. Besides, public awareness and community participation play an important role in the planning process. A variety of diseases can be prevented by improving the provision of water and sanitation and implementing proper drainage and control of disease vectors.
(Dr Mayarani Praharaj works in the Department of Architecture, College of Engineering and Technology, Bhubaneswar)