Administrative Legibility of Urban Green Infrastructure: A Civic–Ecological Translation Index Across Five Cities

Abstract

Urban green infrastructure provides local municipalities a way to speak about parks, rivers, wetlands, coastal areas, street trees, and urban forest systems as public resources rather than incidental spaces. Green infrastructure is, however, not an equal concept throughout cities. While some cities are endowed with significant ecological assets, yet tend to speak using adjacent terminologies like “ecological infrastructure,” “climate adaptation” or “ecosystem services”; others possess less of green cover but are equipped with stronger policy languages that define green infrastructure in terms of planning and infrastructure. The purpose of this paper is to assess the legibility of administrative language in relation to the concept of green infrastructure in five cities—Cape Town, Durban, Johannesburg, Birmingham and London—using the Civic-Ecological Translation Index (CETI). The CETI assessment uses the five parameters of population pressure, ecological endowment, direct green-infrastructure language, balance of stakeholder sectors, and local narrative alignment. Five cities possess the data points of population size, administrative area, green-cover endowment, reference to policy documents and distribution of stakeholder sectors. London leads the pack with CETI of 0.923 due to significant direct language, high pressure from density, wide distribution of stakeholder sectors and National Park City narrative. Johannesburg and Birmingham are at an intermediate stage with CETI scores of 0.663 and 0.646 respectively, though Johannesburg tends to favor use of green resource and provision of services while Birmingham uses natural capital and ecosystem-services language. Cape Town scores 0.524 by use of ecological infrastructure and blue-green service language. Although Durban has 60 percent green cover, its low CETI score of 0.438 indicates that it uses language of adaptation and ecosystem services as a means of environmental management without direct green-infrastructure language in key policy documents.