Maximizing Urban Services in Valdivia, Chile with Green Infrastructure
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Maximizing urban services in Valdivia, Chile with green infrastructure Elizabeth M Cook and Olga Barbosa, Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia Intentional planning with green infrastructure Natural hazards and humans change green Planning for the future in 2030 to protect green may mitigate effects of changing climate infrastructure in Valdivia 2012: Replaced the 2015-2030: predicted infrastructure and reduce vulnerabilities unitary (combined) Cites are increasingly threatened by climate change. Integrating gray 30% urban growth & 1990-2010: 55% sewage & rainwater subsequent loss of The recently published Valdivia Sustainability (e.g. built) and green (e.g. wetlands) infrastructure may increase the 1960: 9.5 magnitude urban growth and system with separate wetlands with business systems using Plan of Action for 2030 highlights normative resilience of cities and urban populations to extreme weather events. earthquake off coast of little regulations led as usual development Valdivia caused 90% to infill of wetlands integrated grey & social, economic and environmental goals for a green infrastructure increase in wetlands for development shared future, including targeted actions to 60 and natural flood and ~70 flood events protection for city protect natural wetlands. 40 Inter-American Development Bank & Initiative for Emerging and Sustainable Cities (ICES) 2015 20 Based on goals in the Sustainability Plan and predicted 30% population 0 growth by 2030, we developed and assessed 3 future scenarios for Valdivia -20 with different strategies for protecting green space and increasing density. Gray (built) infrastructure Green infrastructure Built -40 Wetlands Fail-safe approach minimizing Safe-to-fail approach minimizing Percent Change Grassland -60 Trees chances of failure consequences of failure 1940 1950 1960 1970 1980 1990 2000 2010 2020 2030 High efficiency solutions with Leverages existing natural resources single purpose design to provide multi-functional services 1943 1961 1983 2010 Habitat & Habitat & biodiversity biodiversity Water quality Educational Water quality Educational 2010: Existing 2030: “Business 2030: “Protecting 2030: “Smart regulation value regulation value development as usual” scenario wetlands” scenario growth” scenario No restrictions on Moderate regulations Optimal scenario to Flood Carbon storage Flood Carbon storage Increasing sprawl or future implemented to increase urban regulation & sequestration regulation & sequestration urban development, protect wetlands from density in strategic density including continued infilling for urban hubs and Air quality Air quality infill of wetlands development protect green space Aesthetic & Aesthetic & Figure 2: After a significant increase in wetlands following the 1960 9.5 magnitude earthquake, regulation regulation recreation Thermal recreation Thermal rapid urbanization and lack of development regulations led to the infill and decline of natural value value regulation regulation T. Miller (PSU) wetlands in the city. Historically, wetlands were valued more as cheap land for development Multi-criteria assessment of future scenarios as and waste disposal than for their ecological value. Recently, however, wetlands have been planning and decision support tool Valdivia: a case study of green infrastructure acknowledged in planning documents as valuable flood protection. The optimal “smart growth” scenario may provide greater thermal Latin American cities are particularly vulnerable to climate change and regulation, carbon storage and habitat area than other futures, but extreme events due to rapid urban development, dense populations, have lower flood regulation potential. This highlights the importance of outdated infrastructure, and limited resources. assessing the tradeoffs of multiple services and the need to intentionally We assessed historic and future change in green infrastructure in integrate both green and gray infrastructure in future planning. Valdivia, Chile as a means to mitigate the effects of extreme 2010 Habitat events through the provision of multiple ecosystem services. Assessing multiple ecosystem services over 2030 Scenarios area Figure 4: Multi-criteria Business as Usual 1 Zone 1 time and space assessment of indicators of ecosystem service Zone 2 To quantify impacts of urbanization, we modeled indicators of ecosystem Protecting Wetlands Zone 3 Smart Growth provision of habitat area, Zone 4 services including flood and temperature regulation, habitat area, and carbon carbon storage, and temperature and flood Santiago storage across years (Fig 3A) and vulnerable neighborhoods (Fig 3B). These Flood 1 1 Carbon regulation in 2010 and 3 indicators highlight increasing vulnerabilities to climate change and regulation storage Valdivia future scenarios for 2030 extreme events as green infrastructure and ecosystem services decline (Business as usual, over time and in the most vulnerable neighborhoods (e.g. Zone 3). Protecting wetlands, and Smart growth scenarios). A. Year Habitat B. Urban Area Habitat 1 Ecosystem service area area indicators same as Fig 3. 1943 Zone 1 Thermal Image: NordNordWest 1 1 1961 Zone 2 Figure 1: Valdivia, Chile is ~850km south of Santiago. The city is situated ~15km regulation 1983 Zone 3 from the Pacific Ocean at the confluence of three rivers. Several neighborhoods (Zones 1 - 4) are at high risk for flooding and loss of natural wetlands due to rapid 2010 Zone 4 Next steps toward co-production of desirable development. These areas also house citizens of the lowest socio-economic status. 1 0 1 1 1 future scenarios and cross city comparisons City population: 165,000 Flood Carbon Flood 0 Carbon regulation storage regulation storage We plan to co-produce and assess additional desirable future scenarios City vulnerabilities: Precipitation and tidal flooding, summer drought, with local stakeholders in order to feed into local planning. lack of planning regulations and resources, earthquakes, and landslides. We hypothesize that Latin American cities may be more reliant on green Mean annual precipitation: >1870 mm High/low temperature: 72/40 oF 1 1 infrastructure than North American cities, but incorporate it less formally in Ecosystem: Biodiversity hotspot in Valdivian temperate rainforest Thermal Thermal municipal planning. Thus green infrastructure will be undervalued in Latin regulation regulation American cities for potential to improve ecosystem services. We plan to Figure 3: Indicators of ecosystem service provision modeled (A) over time and (B) in 2010 urban compare cities across a diversity of social-biophysical contexts and neighborhoods most vulnerable to flooding (see Fig 1). All indicators are standardized on 0 (low vulnerabilities to future extreme events (flooding, heat, drought). provision) - 1 (high) scale for comparability. Median flood regulation (runoff potential based on avg Acknowledgements: Many thanks to Javiera Maira (Activa Valdivia), Alexandra Castañeda, Cristóbal García, Karina Godoy, Daniel Harris, 12mm rain event), thermal regulation (evapotranspiration and emissivity), carbon storage (tree C Valeria Ochoa (UACh), and David Iwaniec and Nancy Grimm (ASU). This project is based on support by CONICYT-FONDECYT Projects: 3150290 (Postdoctorado),11110183 & FONDAP: 15110020. storage), and habitat area (% green space) estimated in 6.25 ha grid cells across the urban region. References: Hansen & Pauleit 2014, ICES 2015, Rojas 2006, Shaffler & Swilling 2013, UN Habitat 2012 .