Understanding Green Development and Urban Displacement

Abstract

Nature-based solutions (NbS) such as urban parks, green corridors, and stormwater wetlands are increasingly adopted to enhance climate resilience and livability in cities, yet their social impacts can be uneven. In Cape Town—where apartheid-era planning left certain communities on the under‑resourced Cape Flats while the wealthier people clustered around greenspaces—there is a pressing need to understand whether greening projects might inadvertently displace vulnerable renters. This thesis examines that question by focusing on two contrasting electoral wards: Ward 57, an affluent inner‑city neighbourhood, and Ward 79, the lower‑income Mitchell’s Plain township in the Cape Flats.
To explore how NbS affect housing affordability and demographic composition, a spatially explicit agent‑based model (ABM) was developed for each ward. The city map is discretized into a grid of housing parcels, each with evolving rent levels and ‘livability’ scores that reflect environmental quality, including the presence and maturity of NbS interventions. Household agents—characterised by income, rent‑affordability thresholds, and demographic identifiers—occupy units and face displacement when rising rents exceed their budget or eviction risk thresholds. Vacant units may then be filled by higher‑income in‑migrants. NbS scenarios are introduced exogenously, locally boosting livability scores and triggering rent uplifts that propagate through the spatial grid. Over multi‑year simulations, the model tracks rent burdens, forced displacement events, and shifts in population makeup, enabling side‑by‑side comparison of greening impacts in both wards under a baseline ‘no‑policy’ scenario and alternative housing‑policy regimes.
Results show that, without housing safeguards, NbS raise rents significantly—by roughly 20–25% over ten years—displacing thousands of low‑income households. In Ward 57, this reinforces existing privilege as affluent renters easily absorb price increases, whereas in Ward 79 it displaces predominantly Black African households and Coloured households, substituting them with higher‑income newcomers. Introducing inclusionary housing requirements—which reserve a substantial share of units near NbS sites for affordable rents, dampens rent inflation, retains most incumbent households, and preserves socio‑economic diversity. Time‑limited rent subsidies yield similar short‑term relief but fail to prevent eventual displacement once support expires.
These findings underscore that NbS, while delivering environmental and recreational benefits, can exacerbate urban inequality unless paired with deliberate affordability measures. To achieve just transitions, Cape Town’s green‑infrastructure initiatives should be coupled with inclusionary zoning, dedicated affordability funds, and robust community engagement processes that empower residents and monitor displacement risks. By integrating climate‑adaptation investments with housing‑equity policies, cities can ensure that ecological solutions do not become drivers of social exclusion