The thorny path toward greening: unintended consequences, trade-offs, and constraints in green and blue infrastructure planning, implementation, and management

Abstract

Urban green and blue space interventions may bring about unintended consequences, involving trade-offs between the different land uses, and indeed, between the needs of different urban inhabitants, land users, and owners. Such trade-offs include choices between green/blue and non-green/blue projects, between broader land sparing vs. land sharing patterns, between satisfying the needs of the different inhabitants, but also between different ways of arranging the green and blue spaces. We analyze investment and planning initiatives in six case-study cities related to green and blue infrastructure (GBI) through the lens of a predefined set of questions-an analytical framework based on the assumption that the flows of benefits from GBI to urban inhabitants and other stakeholders are mediated by three filters: infrastructures, institutions, and perceptions. The paper builds on the authors' own knowledge and experience with the analyzed case-study cities and beyond, a literature overview, a review of the relevant city documents, and interviews with key informants. The case studies indicate examples of initiatives that were intended to make GBI benefits available and accessible to urban inhabitants, in recognition of GBI as spaces with diverse functionality. Some case studies provide examples of trade-offs in trying to plan and design a green space for multiple private and public interests in densely built-up areas. The unintended consequences most typically resulted from the underappreciation of the complexity of social-ecological systems and-more specifically-the complexity of the involved infrastructures, institutions, and perceptions. The most important challenges addressed in the paper include trade-offs between the different ways of satisfying the residents' different needs related to the benefits from ecosystem services, ensuring proper recognition of the inhabitants' needs and perceptions, ecogentrification, caveats related to the formalization of informal spaces, and the need to consider temporal dynamics and cross-scale approaches that compromise different goals at different geographical scales.

Mapping mental barriers that prevent the use of neighborhood green spaces

“…The mental mapping study was framed by a quantitative and GISbased study of the UGS infrastructure in the form of pattern, ecosystem flows, and benefits (see methods collection for the ENABLE case studies in Andersson et al 2021), as well as a study of socioeconomic profiles of the (potential) beneficiaries (using census data). Experts in urban planning as well as neighborhood initiatives were consulted for an assessment of the actual UGS in the city as well as new and future developments of UGS, particularly in Halle-Newtown.…”

“…Seen through the eyes of an inhabitant of Halle-Newtown, enabling equal access to recreational functions of UGS in the city of Halle is hampered by physical and infrastructural barriers (see also Kronenberg et al 2021;Wolff, Mascarenhas, Haase et al, unpublished manuscript). At first glance, transportation infrastructures and other physical barriers-offsite such as major roads or distance, boundary such as fences, walls, entrance fees, or onsite such as missing waste bins, benches, light or shadow, as well as rubbish, food leftovers, and drug injecting equipmentseem to be potential candidates for obstacles to the use of local UGS.…”

“…(Map 88). The mental barrier, which we conceptualized in the ENABLE project (see Andersson et al 2021;Wolff, Mascarenhas, Haase et al, unpublished manuscript), exists but does not refer to single or specific features or qualities of the UGS in Halle-Newtown.…”

“…In most of the cases, UGS benefit flows generated by novel green space come from intensively managed, party revitalized, parks, gardens, or leisure spaces, where design and management interpret nature as an easy-to-take bundle of benefits for visitors/ residents (Haase et al 2017, Andersson et al 2021.…”

“…The urban "mental landscape," which includes all the different capacities, understandings, and individual perceptions that urban residents possess and express in relation to their perception of UGS benefit flows (the second and third belong to social infrastructure according to McPhearson et al 2016;Wolff, Mascarenhas, Haase et al, unpublished manuscript). Andersson et al (2021) call these capacities filters, and state "each [SETS] filter is understood as having both direct, individual effects, and a combined interactive effect on the flow and distribution of benefits. "…”