Evaluation Of Urban Expansion And Its Implications On Land Use In Kiambu County, Kenya

ABSTRACT

Rapid urban population growth has led to not only an increasing demand for more land, more so for residential use. This land is not available within the city but at the peri-urban areas where parcels of fertile agricultural land are being converted into residential use at an alarming rate. This is because of the expanding urban area to its urban fringes that is accompanied by an increasing demand for land to accommodate the increasing urban developments. The specific objectives of the research were to, 1) investigate the dynamics of rural land lost to urban land uses in Kiambu County from 1986 to 2014. 2) assess the effects of urban land use changes on agricultural land use in Kiambu County and lastly, 3) to investigate the urban planning and management response to land use changes in northern area of Nairobi. Remote sensed data on land use/land cover change for the period of 1986-2014 together with any historical information and archived reference data used to compute spatial/temporal changes in the expansion of urban settlement and extent of land use/land cover changes. Change detection analysis was performed through GIS overlay operations. The study revealed a significant change of land-use/cover between 1986 and 2014 with the area experiencing rapid increase in urbanization (41.6%), Forest decreased by (10.3%), and a decrease in bare land (1.8%), water (0.22%) and agricultural area (29.3%). Agricultural land in a period of 28 years is losing rapidly to urbanization with the results indicating that 61.5 % of agricultural land converted to built-up land. Declining agricultural land, loss and creation of employment, changing social interaction and lifestyles, increasing land values and housing costs were some of the effects of rural land transformation. The measures put forward to control the rapid land use conversions included zoning for the various land uses. Findings provide a useful support for land-use planning and management. In addition, the results provide necessary inputs to decision makers that should balance trade-offs between the positive benefits of land-use change and potentially negative unintended consequences. The study calls for a combined approach, which involves participation of all the stakeholders in management and planning of land as a vital resource. This approach will protect the endangered land use, agricultural land, as well as controlling urban developments. Based on these results and some observations made in the study area, the study therefore recommends that, stakeholder participation should be given first priority in land use planning and management process, and a cost benefit analysis of land use conversions.