On the impact of urban planning in contexts with limited enforcement of building and planning regulations: A study of the urban form of planned and unplanned informal settlements in Maputo, Mozambique

Background: More than one billion people live in informal settlements under precarious conditions. Urban planning is considered an important instrument to mitigate compromised living conditions in informal settlements. However, limited studies have investigated the long-term impact of urban planning in contexts with limited capacity to enforce building and planning regulations. The purpose of this study is to assess the long-term impact of urban planning on the development of sustainable urban form in contexts characterized by unregulated urban development.

Methods: The study conducted geospatial surveys of three urban areas in Maputo, Mozambique covering adjacent planned and unplanned settlements that were established more than 40 years ago and subsequently developed with limited enforcement of building and planning regulations. High-resolution maps were produced and six urban form metrics were computed for the planned and unplanned areas respectively, providing the basis for quantitative and qualitative comparative analysis.

Results: Although the study found signs of street encroachment and appropriation of the public space in the planned areas, the study found higher levels of built densities, higher proportions of public space, and higher average street widths in all planned areas compared to the respective neighboring unplanned areas. Furthermore, the statistical analysis consistently showed large effect sizes (Cohen's d > 0.8) of urban planning on indicators of compact city development and access conditions.

Conclusion: The results underscore that planning of street fabrics and plot layouts can enhance compact city development, improve transportation conditions, and increase the feasibility of investments in infrastructure in contexts with limited capacity to administer the urban growth.