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1.2 Collection and transfer (Topic b)

How has Africa fared since the end of the Drinking Water Supply and Sanitation Decade in 1989?

1. Coverage

Coverage refers to the percentage of the population that has access to collection and disposal of wastewater, with or without treatment. Table 1.10 indicates that sanitation coverage in the sub-Saharan Africa (SSA) increased from 28% in 1980 to 36% in 1990. Today, access to adequate excreta disposal is available to only about 35% of the population. Technologies used for the safe disposal of excreta are mostly of the individual type, mainly septic tank system and simple latrines. Communal systems, such as conventional and small bore sewers are rare, and available in some urban high income areas only.

In communities where space is lacking, or no nearby reliable water supply is available, the feasibility of water borne sewerage or even pourflush latrines becomes questionable. Households seem to be more aware of these limitations than many technical agencies. For example, in Kumasi, Ghana, more than 50% of households preferred a ventilated latrine to a water-flushed toilet, because the former does not depend on water, is simple and does not break.

The population of Botswana is over 200,000 and still growing at 12% per annum. The capital Gaborone is fully sewered, but roughly half of its households have chosen not to connect to it. This is largely due to affordability, for in-house water and sewerage connection raises SHHA plot cost by 18%.


Table 1.10: Water supply and sanitation coverage in Africa
(a) Coverage for all sanitation types

Water (%)















(b) Coverage of full waterborne sewerage connections in some countries

Country/urban centre % population connected Remarks
Botswana/Gaborone 50 Available access is 100%; length of sewer is 1.85 km /1000 persons
Ethiopia 7  % of national population
Ethiopia/Addis Ababa  12  
Ghana/Accra 3.3 See Table 10.
Kenya/four towns 100 DANIDA project: Busia, Homa Bay,Isiolo and Nyahururu .(See Table 22).
Malawi/all urban areas 15 1987
Nigeria/Abuja Wupa 100; whole territory (75)   Abuja City in Wupa drainage district houses 200,00 people.
Nigeria/Lagos 5 Metropolitan Lagos.
Nigeria/Lagos/Festac Town 100 Population of 90,000
South Africa/all towns and cities 64.2 Ratio of all urban population (totalling24.5 million in 1990.
South Africa/North Cape 29.9 For the whole province.
South Africa/Western Cape 85  Out of a total urban population of 3.156 million in the province.
Zimbabwe/Harare  ~ 100  High income dwellers who have large plots of >2,000m2 are allowed to have preferred septic tanks; length of sewer is 4.1 km/1000 persons
Note: Blantyre and Lilongwe each has a water board. Donor environment appears favourable: as many donor organizations have provided financial assistance through grants and loans The donors include World Bank, UNICEF, UNDP, USAID, DANIDA, EEC, ADB, CIDA, British and French governments.

In 1992 per capita water consumption in Harare was 73 l/c/d for high density, 200 for medium and 311 for low density residents. On the average Harare water users pay $0.15/m3, less than 25% of the real marginal cost of the water. The price of Harare water is based not on its cost, but on the anticipated annual expenditure.

Virtually all the inhabitants of Harare’s recognized residential areas - low and high density - have access to water-flushed toilets and almost all those who need to be connected to sewers are connected. High income dwellers who have large plots of 2,000m2 or more are allowed to have septic tanks if preferred. This is an achievement not matched by any city with such a low GDP per capita.

When Gaborone was established in the mid-1960s, practically the whole of it was sewered by a system of gravity sewers, with treatment facilities in a series of waste stabilization ponds. Everyone could be connected to the sewer system, but not all have been connected. The non-SHHA plots with roughly 50% of Gaborone’s population, have water-borne flush toilets attached to the sewer system. The SHHA plots (low-cost or low-income housing) with the other half of the population, have pit latrines in their yards.

The core of every SHHA plot not connected to the sewer seems to be the VIP toilet. Sludge removal frequency is once in 2-5 years, but in Gaborone, some pits have to be emptied once a week and many of them once in a year.

Both Harare and Gaborone are fully sewered in the sense that almost everyone could be connected up to the existing system. The length of sewer system in Harare is 4.10 km per 1000 population, and Gaborone 1.85 km per 1000 persons.

The population of Addis Ababa is some 2.113 million. A sewerage system was commissioned in 1981 to serve only the central part of Addis Ababa. It is a small system with a capacity to serve only 200,000 users, but is not operating at full capacity. The treatment plant is located at Kalitie and was designed for just 50,000 people, but can be expanded to serve 100,000 and then 150,000-175,000 (World Bank, 1997).

The excessive growth of Dar es Salaam (8% p.a.) over-stretched the drainage system and flooding frequently disrupted economic activities. In 1987 President Nyerere had to intervene personally to immediately effect maintenance work on the sewer network and drains. At that time most of the sewer network was completely blocked by materials and only 2 of the 17 sewage pumping stations were functional. Indeed, only 12% of Dar es Salaam’s population had access to the choked sewers by the early 1980s while 8% used septic tanks and 80% had pit latrines (Oyebande, 1990).

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