Urbaniization in CMA

When considering urban growth in metropolitan areas, polycentric urban structures have been significantly observable everywhere, both in developing and developed nations. Morphological urban developments have been considered in many studies, and recently, attention has been paid to polycentric cities. Polycentricism is a collective concept that works at local, regional, and national levels. However, the development of polycentric urban spaces includes a multitude of decentralized morphologies and functional properties that have significant impacts. Colombo, as Sri Lanka's only metropolitan area, is crucial to investigating the polycentric spatial growth due to the absence of sufficient data. This study was conducted using multi-source data, a geographic information system, spatial analysis, and a network model. It was revealed that Sri Lanka’s urban pattern has changed into urban sprawl through the study period of 1988 to 2022. Due to the urban pattern, the city has been turned into a polynuclear city, making it difficult to identify centers and their level of development. However, the study conducted to identify morphological and functional Grama Niladari divisions revealed that morphological characteristics show centralized dispersion and functional characteristics show decentralized concentration. Therefore, spatial planners must pay attention to this fact when planning the city to achieve sustainable development goals.