Quantifying the commons

The adoption of the New Urban Agenda and the 2030 Sustainable Development Goal 11, specifically target seven that states that 'by 2030, provide universal access to safe, inclusive and accessible, green and public spaces, particularly for women and children, older persons and persons with disabilities' has been instrumental in bringing to the fore public space as a key lever for sustainable urban development. This will require a concerted effort of governments on different levels (national and local) to be able to measure the quality, quantity and distribution of safe, inclusive and accessible, green and public spaces.

The value of public spaces is often overlooked or underestimated by policy makers, leaders and developers. There are a number of reasons for this, such as the lack of resources, understanding or capacity to use the possibilities of public space as a complete, multi-functional urban system. Often the lack of appropriate enabling frameworks, weak political will and the absence of the means for public engagement compound the situation. Therefore, to inform on how to improve a city's supply, quality and distribution of public spaces and to define 'this is where we want to go' requires that we know where we are now. Very few cities possess reliable and updated methods to determine the amount of public space available per inhabitant and, even more important, on the distribution of public spaces in different sectors, districts and types of settlements.

In most cases, a thorough city-wide survey will reveal that both the quality and supply of public spaces decreases in connection to two parameters: average income of residents and distance from the city center. While surveys and maps can offer a general picture of the position and type of public spaces in a city, indicators are numeric expressions that can offer useful information on the availability and quality of public spaces and help identify performance targets for the future measuring: supply, quality, distribution and accessibility.

The results of a city-wide assessment of public space will also provide a basis for the development of a city-wide strategy/action plan on public space as well as define the resources required for its implementation and the legal revisions required to be able to protect and manage those spaces and finally to set up a framework for the land value capture and sharing to ensure that new public spaces are created for the most disadvantaged communities and management of those spaces are sustainable. Without a clear strategy/policy, it is difficult for local governments to prioritise, spend and plan resources and to show how much public space is valued, and to mitigate the negative impacts of site specific interventions (e.g. gentrification). The aim of the city-wide public space assessment tool is to guide policies and strategies at city level.