FUZZY LOGIC MODELING FOR SUSTAINABLE URBAN DEVELOPMENT IN MAKKAH, SAUDI ARABIA

Urban sprawl, which can be defined as unplanned urban expansion that might degrade the environment and influence the aesthetic view, is a persisting problem in Makkah – the third populated city in Saudi Arabia. It is driven by multitude of processes involving the random expansion in undeveloped lands and the removal of mountainous topographic features surrounding Al-Masjid Al-Haram to push the limit of urban capacity within Makkah boundaries. These widespread practices allowed uncoordinated urban growth and dramatically changed the face of Makkah over years. Three to four million Muslims from around the world visit Makkah yearly for religious dedications and undoubtedly, they prefer to observe its bare nature instead of sky scrapers and random subdivisions nearby the holly historical places. However, there is still a pressing need for urban expansion due to the significant increase in numbers of inhabitants and visitors in recent years. According to the 2010 demographic survey conducted by the Saudi General Authority for Statistics, the population of Makkah city was 1,684,408 (including non-Saudi inhabitants). In an attempt to help the city planners and decision makers with the sustainable urban development of Makkah, we have employed a fuzzy logic that assigns weights between zero (fully excluded) and one (fully included) to continuous variables (raster cells) in fuzzy sets defined based on desirable criteria for sustainable urban development. The modeling procedure has incorporated proximity to the holly places, highways, major streams, and existing urban centers and has considered protection to the green spaces and the aesthetically pleasing views of the landscape. The ultimate fuzzy overlay of the desired criteria has identified optimal sites suitable for urban growth mainly in the western, southwestern, and northern divisions of Makkah city. Our results support informed urban expansions that can help avoid periodical flash floods, reduce congestions near midtown, and cease urban sprawl in Makkah city.