**10. Water resources development strategy**

The ACA is divided into three areas in terms of water supply zones, such as Nairobi surrounding area, Mombasa surrounding area and other area for urban water supply systems (UWSS) considering the characteristics of the three areas. The present study, which is in line with the JICA report, noted that in overall Urban Water Supply Systems (UWSS) are planned for 32 Urban Centres (UCs) within the basin. Out of the 32 UCs, 16 are planned for Nairobi and satellite towns and nine UCs in Mombasa and coastal surrounding area while one water supply system is planned to cover several UCs.

The projected water supply capacity required for UWSS in ACA in 2030 is 2,260,000 m3 /day against the current water supply capacity (including capacity under construction) of 699,000 m3 /day. This implies that, additional capacity of 1,560,000 m3 /day need to be developed by 2030. This is proposed to be undertaken through the following three types of projects as recommended in the JICA [1] report.


The development strategy of water resources in ACA for the proposed UWSS is presented in **Table 10**, while those proposed for LSRWSS and SSRWSS are in

*A Critical Analysis of the Water Quality Impacts on Water Resources in the Athi River… DOI: http://dx.doi.org/10.5772/intechopen.99667*


*Note: The water supply development plan of ACA includes Thika with 0.51 million population in 2030. Thika is located in TCA, but it has been covered by water supply system in ACA. LSRWSS- Large Scale Rural Water Supply System and SSRWSS- Small Scale Rural Water Supply System. Source: JICA Study Team [1].*

#### **Table 10.**

*Proposed water supply development plan (ACA).*


#### **Table 11.**

*Water supply situation in 2030 (ACA).*

**Table 11**. This further demonstrates the situation of urban centers subject to urban water supply system development.

The proposed water supply development plan for ACA is outlined **Table 10**.

It is anticipated that by using the water supply development plan indicated in **Table 10**, the water supply situation of ACA in 2030 will be improved as shown in **Table 11**.

The present study proposes the construction of the eight and five dams within the ACA and TCA respectively as noted in the JICA report [1]. This coupled with the expansion of the inter-basin transfer system from the Tana River Catchment Area (TCA) will ensure adequate water supply to both Nairobi city and its environs will be met.

Three new dams in ACA and expansion of two existing intra-basin water transfer systems are envisaged to increase water supply systems in Mombasa city and the coastal area. More dams are further proposed to cover other areas within the Athi River catchment area (ACA). These efforts are likely to increase land under irrigation within the basin and further help in the improvement people's livelihoods in the basin.
