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KAAWANGA 2003 The impact of urbanization on sanitary conveyances and sewage treatment facilities in the city of Lusaka Zambia

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KAAWANGA 2003 The impact of urbanization on sanitary conveyances and sewage treatment facilities in the city of Lusaka Zambia
2
nd
international symposium on ecological sanitation, april 2003
The impact of urbanization on sanitary conveyances and
sewage treatment facilities in the city of Lusaka, Zambia
Obed C. Kawanga
Central Statistical Office
Agriculture and Environment Division
P.O Box 31908, Lusaka, Zambia
e-mail:
[email protected] yahoo.com
Keywords
Conveyances: sanitary drains and sewerage that convey soil, wa ste and storm.
Sanitary facilities: conveyances and treatment systems.
Waste stabilization ponds: which includes facultative anaerobic and maturation ponds they are
biological treatment plant.
Abstract
The overall aim is to promote ecological and sustainable management of sanitation systems in
urban settlements of Lusaka, induce economic growth, health and environmental protection.
The paper brings out information on the status of systems of sanitary conveyances and Waste
treatment facilities. It highlights the impact of urbanization to sanitary infrastructure and the
urban environment. It also shows how poor sanitation has contributed to outbreaks of most
human infections. The paper points out how inadequate design and maintenance of drains
causes rainwater stagnation leading to road damage and breeding grounds for malaria carrying
mosquitoes.
Urban sanitation is a world wide common failure to regard disposal problem as less important
than the consideration of portable water supply. Without effective communi ty-wide method to
contain excremental, the full health impacts of a plentiful water supply will not be appreciated.
The key issues to achieve ecological sanitation are: - political recognition of the importance of
sanitation, poverty alleviation, capacity building, rural economic development (ruralisation) and
the development of policies. Ecological sanitation is eco integration through total cooperation
among decision makers, researchers and the public. It requires systematic planning, adequate
organisation and recycling of urban wastes to prevent environmental damage and health risks.
The increasing and fast growing urban population of Lusaka, Zambia has brought about a
number of adverse effects on the public amenities and environment. At inde pendence (1964)
the population of Lusaka was 195,700. The Population of Lusaka is now estimated at 2 million,
(Central Statistical Office 2000). The sewer network and sewage treatment plants were built in
the late 1950s, with the most development being in 1980 when an extension was made to the
Manchinchi sewage plant.
Despite Lusaka experiencing a rapid growth of population over the last 25 years, no study has
been conducted to determine the effective operation of the sanitary conveyances and sewage
treatment plants (Wamukwamba and Share 2001). These facilities were designed using the
population at that timeserving. Manchinchi and Chunga sewage works design capacity 36,000
and 9,000m3/day, Matero ponds 7,100m3/day, Ngwerere 8,350m3/day, Kaunda square
3,600m3/day, Chelstone 2,700m3/day and Garden maturation ponds 36,000m3/day.
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Introduction
2
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international symposium on ecological sanitation, April 2003
The increasing pressure on existing sanitary systems is reflected in the break down of
conventional treatment plants. Leakages, over loading and chocked sanitary facilities have
resulted into the production of offensive odours (air pollution), contamination of ground and
surface water bodies by spilled un-treated (raw) sewage that poses a health hazard and
degradation of the environment. The city of Lusaka sewer network covers a total len gth of about
450 kilometres with about 10,000 manholes and seven pumping stations in the serviced areas,
which include high, medium and low cost.
The prevailing poor sanitation caused by unsatisfactory operation of sanitary systems has led to
outbreaks of most human infections such as water borne, water based and water related
diseases. These include diseases whose transmission will be reduced following an increase in
the volume of water used for hygienic purposes, like diarrhoeal diseases an example is cho lera.
Water related diseases are these diseases spread by insects which either breed in water or bite
near water, and an example is Malaria.
The poor design and maintenance of the drains (underground and surface) results in stagnation
of rainwater, which contributes to road damage and creates nuisance in the city as well as
creating breeding grounds for malaria carrying mosquitoes. See table 1 showing the top 5 cases
of morbidity in Lusaka in 2001.
No
Causes
Cases
Incident
1
Malaria
32,699
285
2
Diarrhoea
16,534
144
3
Respiratory
13,861
121
4
Pneumonia
7,105
62
5
Intestinal worms
3,171
27
Table 1: Top 5 cases of Morbidity overall in 2001. LDHMT/JICA-PHC April 2002
The conceptual framework in (Diagram.1) shows the importance of collecting data on the
status, the effective operation of sanitary systems and calculated capacities of sanitary
infrastructure. This could be a possible and participatory way of improving sanitation in urban
communities and promoting wastewater reuse, hence, will positively trig ger development in
various aspects of the environment. It is clear from the framework that effective operation of
sanitary facilities can with little doubt lead to: - Improved Sanitation in Urban Communities,
Integrating the Environment to insure the right of citizens to clean and health environment,
Poverty reduction through increasing food production by the use of wastewater by small-scale
farmers and creating employment during maintenance of sanitary facilities. To increase the
effectiveness in the enforcement, there is need to review existing sanitary legislations and
intervention strategies. It also gives a clear understanding of sanitary systems suitable to local
conditions (separate, combine and partially combined systems).
Additional poster
With the framework in mind and the reality of the sanitation situation in the city, it would be fair
to conclude that the effective operation of sanitary facilities can partially, if not wholly prevent
adverse effects brought by poor sanitation in urban serviced communities.
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2
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international symposium on ecological sanitation, april 2003
Figure 1
Justification
The study assessed capacities of sanitary systems and gathered information on status and
satisfactory operation of private and public sanitary conveyances , Waste stabilization ponds and
Conventional treatment plants in relation to the population it is serving. It also assessed the
possible utilisation of wastewater in small-scale farming. Potential risks likely to affect the
communities ware analysed too. The data will be useful in improving sanitation in urban
settlements and review of existing legislation on sanitation. The study is in line with the overall
objective of the National Environmental Action Plan (NEAP): to gather data, which will help to
integrate the environmental concerns into social, economic development and planning process
of the Country. In addition, it is within one of the three fundamental principles of the NEAP '' the
right of citizens to clean and health environment (NEAP 1994).
UNESCO-UNEP, give a world- wide overview on water and sanitation. Lack of safe drinking
water and adequate sanitation for a great number of people in the world is one of today’s most
critical environmental problems. While the estimated water and sanitation coverage is close to
100% in industrialized countries, the situation in t he poor developing countries is far from
satisfactory (Egil 1998).
In 1980, the General Assembly of the United Nations declared the period 1980 – 1990 as the
International Drinking Water Supply and Sanitation Decade. The global target “ Safe drinking
water and adequate sanitation for all people in 1990” was widely published and a mood of
enthusiasm and high expectation was generated. It soon became obvious that the goal of the
decade was unrealistic. However, increased efforts during the decade created awar eness about
the sector and more systematic approach to the problems. Even the goal of the Decade was
clearly unrealistic; two factors particularly had a negative impact on the development. Firstly, the
world population continued to grow rapidly, from about 4.5 billion in 1980 to 5.3 billion in 1990,
with most of the increase (about 614 million) in the developing countries, particularly in urban
areas. Secondly, the downturn in the world economy made fewer funds available for the sector
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Zambia is one of the developing Countries of the World. Developing Countries of the World are
those, that are poor and behind in many things, such as level of education, health service
provision, inadequate sanitation and wholesome water supply to their populat ion. They have
high death rates and high birth rates and their population often increases at such a rapid rate
that they can handily keep up with new jobs. (Monica and Bennett1986).
2
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international symposium on ecological sanitation, April 2003
in many countries. In the early 1970s it was estimated that only one third of the people in the
developing world had access to safe drinking water and adequate sanitary excreta disposal.
Furthermore, population growth and increasing urbanization make the prospects of the decad e
target grim. Inadequate Urban Sanitation, Urbanization is often the major source of pollution of
ground and surface water bodies (Egil 1998). This may be through leaks from sewer pipelines
and sewage treatment facilities.
Inadequate urban Sanitation is worldwide common failure in regard to excremental disposal
problems, which in the developing world the situation is more serious, Zambia inclusive. To
solve these environmental health problems, the Government of the republic of Zambia has
embarked on Environmental Support Program (ESP), which is a long -term commitment to
stimulate the interest and investment in environmental and natural resources management with
the framework of the economic growth. The NEAP has identified five major environmental
issues water pollution and inadequate sanitation, soil degradation, air pollution wildlife depletion
and deforestation. The NEAP is founded on three fundamental principles that is the right of
citizen to a clean and health environmental. Local community and private sector participation in
natural resources Management. Obligatory Environmental Impact Assessment (EIAs) of major
development in all sectors.
The rapid demographic changes especially in urban cities, such as Lusaka are caused by an
annual population growth rate of 3.5%, urbanization, industrialization, increased social
amenities demand and general economic decline, pose a threat to sustainable use of the
natural resources which, in return threatens economic, social and environmental sustainability in
the long run (Central Statistical Office 1990).
The city of Lusaka attracts numerous migrations because of its various small -scale businesses
and both formal and informal employment. However, since the mid 1990s when the country
began to experience serious econo mic downturns job opportunities became very limited and
most migrations ended up in the informal sector. The high level of urbanization taking place in
Lusaka and the constant lack of adequate management of the city have constrained the city
authorities in providing basic services such as adequate road drainage, sanitation, water and
many other public amenities.
Additional poster
A survey conducted by (CSO and University of Zambia 1992), on country profiles identified that
Government has recognized the need to promote and ma intain the welfare of the people by
adopting sustainable policies, for the benefit of both the present and the future populations. An
implementation program to achieve these goals regimes appropriate policies, incentives,
guidelines and public awareness at local, provincial and national levels could be done by
carrying studies and provide information in order to promote citizens right to clean and health
environment and for policy formulation. On urbanization it reported that the high population
concentration in urban centres have put pressure on meagre urban resources especially
sanitary facilities. Most urban municipalities have failed to provide social services such as clean
water, adequate sanitation and waste disposal. Migration into urban centres has lead to the
sprouting of unplanned settlement areas (shantytowns). Inadequate sanitation and lack of clean
water supply pose great health dangers and environmental hazardous. Out breaks of diseases
formerly rare in Zambia such as cholera have now become en demic problems.
(Bland and Kilama 1985) conducted a study to determine the causes of most infectious
diseases; the investigation identified that poor sanitation is the major cause of most human
infections. Infections spread through inadequate sanitation include: viral diseases like cholera,
typhoid, paratyphoid and bacillary dysentery; protozoal diseases like amoebic dysentery and
worm infections like ascariasis, pinworm spread through direct contact, indirect via water, soil
and food or via carriers. The study further finds that; without effective community-wide method
to contain excremental, the full health impacts of a plentiful water supply will not be appreciated.
The major sources of water supply for the city of Lusaka are derived from two sources, gr ound
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2
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international symposium on ecological sanitation, april 2003
water 53 boreholes around the city and surface water from Kafue River. The average annual
production of water is 200, 000 cubic meter with each source accounting for 50% of the
production quantity. Further more, the paper states that the water borne s ewerage systems
cover about 30% of the area to which the company has water supply services and the total
length of about 450 kilometres with about 10,000 manhole. These are usually poorly
constructed or located, posing a risk of contaminating ground water. The areas, which are
serviced, include high cost and medium cost areas (Mtine 2000).
From the foregoing review of literature, it is evident that a number of studies have been
conducted in Lusaka. Most of these have concentrated in the water supply, water quality and
solid waste management. The reviewed studies also show that there are a number of water
projects under taken in Lusaka and elsewhere in Zambia. Therefore, the importance of
conducting this study cannot be over emphasized, if the trend cannot be reversed the quality of
the ground and surface water could be effected and bring about adverse effects to the
environment and human life.
The literature cited indicates that there has been no detailed study to review the status and
satisfactory operation of sanitary Conveyances both (under ground and surface drains) and
sewage treatment facilities in relation to population growth. Therefore the importance of this
proposed study cannot be over emphasized and it requires support, in order to meet the
national goals to integrate the degrading environment.
Methods
Data collection involved review of literature; stakeholder interviews using questionnaires (10
institutions and 300 household core informants), focus group discussions and inspection
(observation) of sanitary systems. Both qualitative and quantitative data was collected. The 30
wards in Lusaka urban were stratified and a sample of 6 wards was selected representing two
(2) wards from each residential category namely high, medium and low -density areas. The
circular systematic sampling method was used in the selection of wards, which assumes the
following relationship: Let N = nK
Where N = total Number of wards assigned sampling serial number s in the case 30 n = The
sample size of wards i.e. the required number of wards, which in this case was 6.
K=
=
30
N
n
/6 = 5
A random Number was obtained from a table of random numbers. This number was between I
and N (both inclusive). In this case, the N was 30, as there were a total of 30 words. The
sample interval K = N n was calculated. In this case was K = 30/5 = 6. The sampled numbers of
wards required were then selected using the circular systematic sampling method. The ward
whose sampling serial number corresponded to the random start was the first selected ward.
Then the K, i.e. the sampling interval was applied by adding K to each selected wards, serial
number until the required sample size ( n = 6wards) was achieved. In all, 6 wards were
selected.
Results
It is evident that Lusaka is the most urbanised, populated c ity in Zambia and one of the
urbanised in sub Saharan Africa. The public sanitary facilities are overloaded because they
were designed with the capacity follow of 36,000 m3/day in 1950s but currently they are serving
more people. The service providers’ are strained due to limited capacity to maintain the existing
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K = The Sampling Interval calculated as
2
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international symposium on ecological sanitation, April 2003
sanitary systems in the city. It was found that extensions are made in private cartilages with or
without permission from the local authorities, especially in low and medium cost areas, see
figure 1. Showing a housing structure extension within a yard, drains and sewer are connected
illegally.
Figure 2:
Building extensions, source: field data 2002
It was evident that the socio-economic and practices of urban communities have contributed to
unsatisfactory operation of sanitary infrastructure in the city. The street vendors use drains to
dispose solid waste most of which are Inorganic nature. The Inorganic substances are trapped
as screens before entering the waste treatment plants. These inorganic materials are usually
block and damage the drains. There are no source separation of solid waste in the city of
Lusaka and most waste generated are indiscriminate damped, especially in low and medium
cost areas. In some case vendors remove lids from the manhole and inorganic waste materials
are found into sewer lines up to the screen. See figure 2, showing inorganic screens.
Additional poster
Figure 3: Screens out for sewer, source: field data 2002
Most infectious diseases common in Lusaka are spread through inadequate sanitation.
Especially malaria, cholera, dysentery, and typhoid have become endemic in urban settlements.
In 1997/1998-rain season, the Central Boar d of Health reported that by February 19, 1999 there
were 1,540 cases of cholera in 14 districts countrywide. There were 43 deaths, 19 of them from
Lusaka alone. Urbanisation has contributed greatly to poor sanitation, which is often the major
source of pollution of the ground and surface water. This is through leaks from sewer pipes,
waste stabilisation ponds and discharge of raw sewage from dilapidated sewer system into
water bodies’ figure 3, showing ponds of sewage fro dilapidated manhole and figure 4 showing
dry up waste stabilisation ponds.
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Figure 4:
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international symposium on ecological sanitation, april 2003
Dilapidated manhole, source: field
Figure 5:
data 2002
Dilapidated
manhole,
source:
field
data 2002
Conclusion
The conclusions drawn are that urban sanitation is a common failure especially in developing
countries like Zambia. The disposal problem of solid and wastewater are regarded as less
important than the consideration of portable water supply. The fact is that without effective
community-wide method to contain excremental, the full health impacts of a plentiful water
supply will not be appreciated. The historical roots of such an assumption originated in times
when it was acceptable to pour the wastewater into the nearest watercourse. Urbanisation is
often the major problem in Lusaka and other cities in developing countries. The concept of
ruralisation is not fully implemented so as to control urban drift. Capacity building and political
will can contribute to improve sanitation situation in urban settlements were leaks from sewer
pipes, waste stabilisation ponds and illegal sewer connections are common.
Regarding developing countries, the key issues to achieve ecological sanitation are: - political
recognition of the importance of sanitation, poverty alleviation and rural economic development
(ruralisation), recycling of urban wastes and the development of adequate policies. Ecological
sanitation is eco integration through total cooperation among decision makers, researchers and
the general public. It requires systematic planning, adequate organisation and recycling of
urban wastes and wastewater to prevent environmental damage and health risks. Efficiency,
equity and vitality are the three dominating agents in ecological sanitation. Ecological sanitation
requires totally functioning design, management and help local people through capacity
building.
References
Central Statistical Office: Census 1990a, 2000b, Lusaka, Zambia.
Egil Skofteland, 1998 (UNESCO-UNEP) Freshwater Resources (By Norwegian Water Resources and
Energy Administration) Oslo, Norway. P32-49
Government of the Republic of Zambia 1994. National Environmental Action Plan (NEAP), Lusaka
Zambia. P viii
LCC and GRZ 1997 an environmental Profile of the Greater Lusaka Managing the Sustainable Growth
and Development of Lusaka. P 10 -25
Monica Byrne and F.J. Bennett 1986 Community Nursing in Developing Cou ntries. P1
Mtine, H. 2000. Water quality and sanitation information management. Zambia. P1 -3
Win bland and Uno Kilama. 1993 Sanitation without water. Stockholm: SIDA. P 5 -11
Wamukwamba C.K and Share 2001. 27th WEDC Conference Lusaka, Zambia. P346
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Central Statistical Office & University of Zambia 1992 Country profile Lusaka Zambia.
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