The Concept of the 15-minute City in the Post-Soviet Space

The 15-minute city concept, which gained attention during the COVID-19 coronavirus pandemic because of the restrictions imposed in many municipalities on the movement of residents, involves redesigning neighborhoods so that each resident has a 15-minute walking or biking distance to meet their needs (education, medicine, green spaces, commerce, etc.). One possible use of the concept as an analytical tool is to construct a specialized index. In this paper, we model pedestrian accessibility to basic services for three post-Soviet cities (Krasnodar, Saratov, Naberezhnye Chelny) differing in dominant morphological types of development. For this purpose, we use open data and 2GIS API data, estimate accessibility using network analysis, compile an index, and evaluate the statistical relationship between it and residential development morphotypes. We find that the location of basic need facilities in the city can be divided into two categories: clustered and dispersed. The best pedestrian accessibility to all facilities is observed in historic city centers, which is associated with the highest concentration of clustered facilities here. Historic development is characterized by twice better pedestrian accessibility than the Soviet apartment development, and three times better than the territories of individual housing construction. Differences in building morphology also determined differences in accessibility between the three cities studied. From one third to one half of the population of Saratov and Krasnodar live in the zone of 15-minute cities, and in Naberezhnye Chelny - 75% of the population. In the case of modeling with only dispersed facilities, between 86% and 92% of the population of the three cities studied fall within the 15-minute coverage zones. The accessibility index of objects developed in the study and its spatial location can be used in planning the location of new objects of social importance, in planning the location of new housing, in evaluating the comfort of the urban environment.