Planning gaps: unexpected urban expansion in five Colombian metropolitan areas

Colombia has experienced rapid urbanization over the past three decades. Most Colombian cities doubled their urban extent in the last 10 years which resulted in a high demand for land. This research identifies urban expansion patterns in five of the largest urban agglomerations in Colombia. Urban growth is analysed using satellite images (Landsat 5) and census data to assess spatiotemporal land-use changes over a 30-year period (1990–2020). The actual urban extents are compared with each city’s land-use predictions, instruments, and regulations to ascertain whether local authorities have the capabilities to predict land demand and to guide development processes at the municipal level. The predictions made by local authorities are inaccurate and often underestimate the rates of population growth and land requirements. The findings reveal that local authorities lack the capabilities to manage urban growth and deliver sustainable urban development. This is leading to poor outcomes: low planning standards, urban informality and inefficient land use. Policy relevance This research reveals a significant gap between urban land-use policy instruments and actual urban growth patterns in Colombian cities. The findings reveal that the current urban expansion surpassed what local authorities had anticipated and allocated for land use. Although existing policies empower local authorities, their capabilities to effectively monitor and model population growth and associated land requirements are poor. This led to an underestimation of land requirements and poor planning outcomes. To improve future decision-making and management of urban growth, urban planners should use empirical data to inform urban growth scenarios: allocate sufficient land to allow for orderly growth, designate specific areas for development and provide for sufficient infrastructure.