Overview 9
Figure 3 Proposed Staged Development of Alternative Water Sources in Nairobi, Kenya, 2010 to 2035 Water demand
Water demand/supply, m3/d
1,400,000 1,200,000 1,000,000 800,000
Private boreholes
Existing water wupply
Water demand management
Leakage management
Future water supply sources Stormwater harvesting (cluster)
Mathioya transfer to Thika Greywater (cluster)
Kiunyo well fields Ruiru well fields Northern Collector I
600,000 400,000 200,000
Existing water supply
20 12 20 13 20 14 20 15 20 16 20 17 20 18 20 1 20 9 20 20 2 20 1 22 20 2 20 3 24 20 2 20 5 26 20 2 20 7 28 20 2 20 9 30 20 3 20 1 32 20 3 20 3 34 20 35
0
Year Source: World Bank. Note: The figure shows the years at which the different water sources need to be developed to meet the growing water demand for Nairobi. The volume of water supplies from each source has been determined based on meeting medium-term water demand projections. Some of the sources might need to be developed at the same time (for example, Northern Collector 1 and water demand management; leakage management and stormwater harvesting). m3/d = cubic meters per day.
leakage reduction, water demand management, stormwater and rainwater harvesting, and greywater recycling may provide added flexibility and resilience (see Figure 3). Some of these sources are seasonal in nature, but with carefully designed storage facilities, such a solution may also provide additional resilience to prolonged droughts and climate change. Horizontal integration of planning and integration across spatial boundaries is possible with a concerted effort and national support. Polokwane, the capital of Limpopo province in South Africa, has put in place a water strategy that emphasizes building capacity to strengthen the coordination of water use and supply, water safety plans for catchment areas, a drought management plan including increased use of recycled wastewater, demand management, as well as a pressure reduction system to reduce water leakage, and a price structure to encourage water savings. Critical to the success of IUWM is the early and continuous involvement of all stakeholders—including the public—in the planning, decision-making, and implementation process. Stakeholder and public participation can improve the scope of decision making and can help to