DESIGN AND APPLICATION OF SYSTEM DYNAMICS MODEL FOR DOMESTIC WATER SECURITY IN INFORMAL SETTLEMENTS IN NAIROBI COUNTY, KENYA

Abstract

Attainment of water security in urban informal settlements in developing countries can be complex undertaking due to various factors that affect water service provision such insufficient water quantities, unreliable water supply, aging pipes, infrastructure coverage among others. In addition to this, the territorial behaviour and therefore a siloed approach of service providers propagates water insecurity. This situation has an impact on the socio economic development, peace and political stability, water related disasters and waterborne diseases in many urban informal settlements in developing countries. The study sought to develop and apply a System Dynamics Model to help identify specific policies that will improve water security in the informal settlements. Data was collected from a sample of 388 households and 62 water vendors from nine slums in 12 sub-counties. Household questionnaire, KII, FGD guide, and observation checklist were used to collect data. Specifically, the study assessed water security characteristics in informal settlements in Nairobi County; evaluated the structure of the system of water service provision; evaluated water service provision integration approaches on water security; and finally, developed a system dynamic model to articulate the structure and function of a water supply system. From the findings, only 0.4% households met all the six parameters (availability, access, quantity, quality, affordability and reliability) of water security. Most of the households, 31.8% satisfied four parameters, 30% met three parameters, 20.8% met two parameters, 11.7% met 5 parameters and 5.3% met one parameter. This pointed to a situation where water security is a major concern in Nairobi’s INSEs. The existing water structures of service provision influenced only three of the six water security factors, and that is, availability, access, and quality. The level of structure did not have any impact on quantity, affordability, reliability of water services. The study therefore concludes that, provision of infrastructure alone may not necessarily lead to overall household water security. The research findings show that, integration is possible along the three levels, water production, water delivery infrastructure, and service levels experienced by the households. It was however noticed that a household could depend on multiple sources and therefore experience various levels of services. From simulation of various scenarios, the integrated water service provision model (IWSP-M), reveals that it will be difficult to resolve water security in Nairobi’s informal settlements without integrating the small-scale water service providers with those of NCWSC. Equally, reduction of Non-Revenue Water, drilling of high-yield boreholes and proper maintenance of reservoirs will help reduce water stress and therefore lead to improved domestic water security. The interactive IWSP-M allows for deep exploration of the cause-and-effect feedback loops between households and the systems governing water services in INSEs within Nairobi County. This will help policy makers on investment and targeted resource allocation. On the other hand, water service providers can use the results to have a better understanding of the existing potential for integration of services to improve water security in informal settlements.