What is Adaptive Water Urbanism?
Adaptive water urbanism is a water-centric, systems-based approach to resilient place-making. This design approach intends to help adapt cities and regions to more intensive storms, more sustained drought, more severe land subsidence, and a rising sea level. Adaptive water urbanism also addresses environmental adaptation by making cities and regions more livable socially, economically, environmentally, ecologically, and aesthetically as co-benefits of climate adaptation. Specifically, a divide-and-conquer approach is often undertaken to untangle the compounding effects of inland, riverine, and coastal flooding so that the impact of each flooding source can be attenuated as locally as possible.
Key Characteristics of Adaptive Water Urbanism as a Resilient Urban Design Approach
“No-regret” strategies. Large-scale monofunctional structural solutions are expensive, irreversible, yet less adaptable to an uncertain future. It is beneficial for cities and regions to explore “no-regret” strategies for climate adaptation because they provide immediate co-benefits in case a particular design target event does not take place in the future. Adaptive Water Urbanism engages communities to conceive “no-regret” strategies as adaptable systems composed of decentralized ecosystem-service providers (ESPs). These ESPs are not only water-centric urban design features but also building blocks for long-term regional resilience. Similar to ecological succession in nature, adaptive water urbanism phases design solutions so they evolve as the impacts of climate change unfold. For example, this approach may consider designs that will facilitate emergency response in the short-term while allowing ecosystems and communities to adapt to mid-term and long-term solutions that will likely become imperative to our collective survival as the impacts of climate change full take hold. To address the uncertainty in climate science, scalable solutions are better suited for the near future because they can be adjusted to the actual climate impacts. Adaptive water urbanism emulates patterns seen in nature, such as decentralized systems with redundancy, because they tend to be the most efficient resilient forms. Due to the shortage of proactive funding for climate adaptation, it is important for revenue-generating activities to be incorporated in earlier phases to help finance subsequent phases and to synergize with capital improvement projects in the pipeline.
Prototypes. Adaptive water urbanism explores these decentralized ESPs as prototypes. A prototype is a form-based preliminary concept with some level of materiality. A prototype can be tested and replicated as experiments or made spatiotemporally responsive to varying climatic conditions, site factors, and future scenarios. Adaptive water urbanism optimizes the multi-functional (hydrological, social, economic, ecological, and aesthetic performance) of each prototype before making it part of a spatiotemporally specific design response.
Systems. We share the essence of adaptive water urbanism prototypes with the public as design game cards. Design game cards are used to engage experts, high school students, stakeholders in generating consensus-based solutions that interconnect adaptive water prototypes into a larger landscape infrastructure system. We then synthesize the outcomes of design games into an urban design framework that helps coordinate adaptive designs at varying nested scales as kit-de-parts to maximize the multi-functional (hydrological, social, economic, ecological, health, and aesthetic) performance of the landscape infrastructure system.
Adaptation Pathway. To design for future uncertainty, design games are conducted to investigate alternative futures derived from different adaptation attitudes (emergency evacuation, adaptation in-situ, and proactive relocation) and scenarios (best-case and worst-case) to address existing and future challenges along a timeline with 2018, 2030, 2050, and 2100 as phasing benchmarks. These challenges can be instantaneous, such as explosions of refineries and reservoir dam breaks, and incremental, including more intensive storms, more sustained drought, more severe land subsidence, more widespread sewer backup, and a rising sea level. Instantaneous events typically involve emergency evacuation while incremental risks can potentially be eliminated through proactive relocation from potential impact zones. The worst-case scenario assumes that all instantaneous and incremental challenges materialize in the future although some of them could have been avoided through removing relevant man-made triggers, such as refineries and reservoirs. On the contrary, the best-case scenario suggests that human efforts have been made to remove these man-made triggers, to prevent instantaneous incidents from occurring and to minimize the impacts of incremental events to the extent possible.
Multi-Species Adaptation. Non-human species displaced by flooding are also in search of emergency shelters and relocation destinations on safer higher ground. In most cases, they co-exist with evacuated humans harmoniously. However, in Houston, alligators, fire ants, and snakes, became hazards to humans as they lurked in recreational water bodies in urban settings and showed up on private properties after Harvey. Many wetlands species will become extinct as the sea level rise pushes the water level beyond their comfort zone. They will need elevated habitats to migrate to as permanent inundation zone gradually expands with sea level rise. A multi-species approach to both climate and environmental adaptation is critical for helping both human and non-human refugees adapt to a new environment.
Multi-Systems Resilience. Flood vulnerability often results in public health vulnerability beyond the immediate flood-prone areas. While some humans and non-human species in those communities may gradually lose their habitats to rising tides, others can be severely impacted by inundation-induced explosions and overloading of toxics into water, land, and air when chemical plants and refineries are damaged by flooding. On the other hand, not all socioeconomic groups are equally equipped to evacuate and to recover from a flash flood or the public health impacts of flooding. The elderly and the disabled may be left behind during emergency evacuation because they have limited physical mobility or no transportation means. Underrepresented groups face more challenges financially and socially during and after flood events. Support networks and place attachment have been found to help climate refugees recover faster from disasters. Multi-criteria analyses are conducted to identify resilient and vulnerable communities by examining the hydrological, social, and public health systems of geographic information.