Sanitation and Wastewater Atlas of Africa

urban extent in 2018 wetland extent in 1996 Urban extent in Kampala and Entebbe in 1995 and 2018 urban extent in 1996

Agr icul ture Agriculture, together with construction, leads to the clearing of forests around the lake. With less forested area, the volume of runoff water increases. In addition, farmers are using large proportions of inorganic fertilizers, which contribute to the phosphorus and nitrogen loads that Murchison Bay receives. This creates an environment that is nutritionally rich for the uncontrolled spread of plants like the water hyacinth.

Roads Compounds, landing sites, footpaths and unpaved roads are significant sources of pollution into the lake and they also contribute to soil loss.

Indust r ies The fish-filleting industry and tanneries in Kampala contribute a significant nitrogen and phosphorus load to the lake. The industrial BOD released into the bay is of 2520 kg/day, which is only a fifth of the municipal BOD load that is of 14116 kg/day.

1,982

Wastewater management Water treatment costs are raised by the increased pollution of the bay. The wastewater discharge point, at the tail end of the system comprising two sewage treatment plants, is only 2 km away from the raw water intake point of the city.

Kampala

Wet lands Wetlands help bring down the levels of pollution that reach Lake Victoria by increasing the rate of self-purification of the effluents from the destruction of pathogens and the using up of nitrogen and phosphates (60 to 90% removal) by the aquatic plants in the swamp. The reduced speed of waterflow allows for sedimentation of suspended solids, and this controls the turbidity of the lake water.

Murchi son bay

Entebbe

Kampala and Entebbe are among the most polluting cities around the lake contribut- ing a BOD above 9000 kg/day and above 1600 kg/day, respectively. Mean pollution loads (BOD) discharged into the lake in kg/day:

Kome Island

Kampala 9,153 kg/day

d a

Jinja

K e

a n

Entebbe 1,982 kg/day

n y

U g

LAKE VICTORIA Main source for water of Kampala City. The lake also receives 60% of the pollution generated by Kampala City

a

Kakamega Mumias

Kisumu 2,749 kg/day

Masaka

Migori

LAKE V ICTOR IA

Nak i vubo channe l The channel and its tributaries traverse the Makerere Kivulu slum, markets and the Kampala industrial area before ending up in the Murchison bay. Due to poor building practices and regulations, the channels are often connected to sewer pipes. The daily wastewater load that the channel contributes to the Lake corresponds to 0.2% of the volume of water that enters Murchison bay.

Bukoba

Musoma

Geita

i a

a n

n z

Mwanza 5,359 kg/day

T a

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SANITATION AND WASTEWATER ATLAS OF AFRICA