2 SUSTAINABLE URBAN SYSTEMS

A devastating cholera epidemic swept Zimbabwe in 2008, causing over 90,000 cases, and leaving more than 4,000 dead. The epidemic raged predominantly in urban areas, and the cause could be traced to the slow deterioration of Zimbabwe's water and sewerage utilities during the economic and political crisis that had gripped the country since the late 1990s. Rapid improvement was needed if the country was to avoid another cholera outbreak. In this context, donors, development agencies and government departments joined forces to work in a unique partnership, and to implement a programme of swift improvements that went beyond emergency humanitarian aid but did not require the time or massive investment associated with full-scale urban rehabilitation. The interventions ranged from supply of water treatment chemicals and sewer rods to advocacy and policy advice. The authors analyse the factors that made the programme effective and the challenges that partners faced. The case of Zimbabwe offers valuable lessons for other countries transitioning from emergency to development, and particularly those that need to take rapid action to upgrade failing urban systems. It illustrates that there is a ‘middle path’ between short-term humanitarian aid delivered in urban areas and large-scale urban rehabilitation, which can provide timely and highly effective results.

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Landscape Design toward Urban Resilience: Bridging Science and Physical Design Coupling Sociohydrological Modeling and Design Process

Sustainability ◽

10.3390/su13094666 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4666

Author(s):

Yoonshin Kwak ◽

Brian Deal ◽

Grant Mosey

Keyword(s):

Pilot Study ◽

Landscape Design ◽

Urban Systems ◽

Urban Resilience ◽

Planning Support Systems ◽

Creative Solutions ◽

Resilient Communities ◽

Study Support ◽

Key Variables ◽

Resilient Design

Given that evolving urban systems require ever more sophisticated and creative solutions to deal with uncertainty, designing for resilience in contemporary landscape architecture represents a cross-disciplinary endeavor. While there is a breadth of research on landscape resilience within the academy, the findings of this research are seldom making their way into physical practice. There are existent gaps between the objective, scientific method of scientists and the more intuitive qualitative language of designers and practitioners. The purpose of this paper is to help bridge these gaps and ultimately support an endemic process for more resilient landscape design creation. This paper proposes a framework that integrates analytic research (i.e., modeling and examination) and design creation (i.e., place-making) using processes that incorporate feedback to help adaptively achieve resilient design solutions. Concepts of Geodesign and Planning Support Systems (PSSs) are adapted as part of the framework to emphasize the importance of modeling, assessment, and quantification as part of processes for generating information useful to designers. This paper tests the suggested framework by conducting a pilot study using a coupled sociohydrological model. The relationships between runoff and associated design factors are examined. Questions on how analytic outcomes can be translated into information for landscape design are addressed along with some ideas on how key variables in the model can be translated into useful design information. The framework and pilot study support the notion that the creation of resilient communities would be greatly enhanced by having a navigable bridge between science and practice.

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Modeling the Impacts of Autonomous Vehicles on Land Use Using a LUTI Model

Sustainability ◽

10.3390/su13041608 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1608

Author(s):

Rubén Cordera ◽

Soledad Nogués ◽

Esther González-González ◽

José Luis Moura

Keyword(s):

Land Use ◽

Urban Sprawl ◽

Autonomous Vehicles ◽

Interaction Model ◽

Urban Systems ◽

Unwanted Effect ◽

Urban Center ◽

Positive Effects ◽

Current Paradigm ◽

Shed Light

Autonomous vehicles (AVs) can generate major changes in urban systems due to their ability to use road infrastructures more efficiently and shorten trip times. However, there is great uncertainty about these effects and about whether the use of these vehicles will continue to be private, in continuity with the current paradigm, or whether they will become shared (carsharing/ridesharing). In order to try to shed light on these matters, the use of a scenario-based methodology and the evaluation of the scenarios using a land use–transport interaction model (LUTI model TRANSPACE) is proposed. This model allows simulating the impacts that changes in the transport system can generate on the location of households and companies oriented to local demand and accessibility conditions. The obtained results allow us to state that, if AVs would generate a significant increase in the capacity of urban and interurban road infrastructures, the impacts on mobility and on the location of activities could be positive, with a decrease in the distances traveled, trip times, and no evidence of significant urban sprawl processes. However, if these increases in capacity are accompanied by a large augment in the demand for shared journeys by new users (young, elderly) or empty journeys, the positive effects could disappear. Thus, this scenario would imply an increase in trip times, reduced accessibilities, and longer average distances traveled, all of which could cause the unwanted effect of expelling activities from the consolidated urban center.

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Harmonized assessment of nutrient pollution from urban systems including losses from sewer exfiltration: a case study in Germany

Environmental Science and Pollution Research ◽

10.1007/s11356-021-12440-9 ◽

2021 ◽

Author(s):

Hong Hanh Nguyen ◽

Markus Venohr

Keyword(s):

Pollution Control ◽

Expert Knowledge ◽

Age Factors ◽

Urban Systems ◽

Nutrient Pollution ◽

Extended Model ◽

Urban Wastewater ◽

Model Framework ◽

Public And Private ◽

Wastewater Systems

AbstractA growing literature indicates that untreated wastewater from leaky sewers stands among major sources of pollution to water resources of urban systems. Despite that, the quantification and allocation of sewer exfiltration are often restricted to major pipe areas where inspection data are available. In large-scale urban models, the emission from sewer exfiltration is either neglected (particularly from private sewers) or represented by simplified fixed values, and as such its contribution to the overall urban emission remains questionable. This study proposes an extended model framework which incorporates sewer exfiltration pathway in the catchment model for a better justified pollution control and management of urban systems at a nationwide scale. Nutrient emission from urban areas is quantified by means of the Modelling of Nutrient Emissions in River Systems (MONERIS) model. Exfiltration is estimated for public and private sewers of different age groups in Germany using the verified methods at local to city scales, upscaling techniques, and expert knowledge. Results of this study suggest that the average exfiltration rate is likely to be less than 0.01 L/s per km, corresponding to approximately 1 mm/m/year of wastewater discharge to groundwater. Considering the source and age factors, the highest rate of exfiltration is defined in regions with significant proportions of public sewers older than 40 years. In regions where public sewers are mostly built after 1981, the leakage from private sewers can be up two times higher than such from public sewers. Overall, sewer exfiltration accounts for 9.8% and 17.2% of nitrate and phosphate loads from urban systems emitted to the environment, which increases to 11.2% and 19.5% in the case of no remediation scenario of projected defective sewer increases due to ageing effects. Our results provide a first harmonized quantification of potential leakage losses in urban wastewater systems at the nationwide scale and reveal the importance of rehabilitation planning of ageing sewer pipes in public and private sewer systems. The proposed model framework, which incorporates important factors for urban sewer managers, will allow further targeting the important data need for validating the approach at the regional and local scales in order to support better strategies for the long-term nutrient pollution control of large urban wastewater systems.

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Health in cities: Getting out and about as we age

European Journal of Public Health ◽

10.1093/eurpub/ckaa166.093 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

T Ma ◽

R Ivers ◽

E de Leeuw ◽

K Clapham ◽

C Kobel

Keyword(s):

Older People ◽

Policy Making ◽

Urban System ◽

Transportation Systems ◽

Social Contexts ◽

Urban Systems ◽

Activity Levels ◽

The Public ◽

Housing Developments ◽

Health Community

Abstract Transportation influences health through its effects on people's access to goods, services, and life chance opportunities; social interactions; physical activity levels; air pollution exposures; and road injury risks. Given the ageing of populations, it is essential that decisions about land use and transportation systems are appropriate to meet the mobility needs of older people and support healthy ageing. Not all transportation options, however, may be accessible to older people. Factors that affect accessibility relate to the spatial and physical characteristics of places, personal and social contexts of individuals, and rules and norms underpinning planning and policy making. This research aimed to understand how different parts and processes of urban systems interact to influence transportation options for older people. Using the Greater Sydney area as a case, we drew on key informant interviews and public policy documents to identify the considerations that inform planning and policy making as they pertain to the nature of cities and the opportunities of older people to get out and about. We compared and integrated these findings with peer-reviewed literature of similar urban growth areas. Our analysis mapped the factors of the human-urban system that are central to enabling transportation mobility for older people, articulated their interrelationships, and identified the actors that influence them. Our results point to the involvement of actors from the public health, community development, transportation, and urban planning sectors at multiple levels of government. Each of these actors operate within their own remit to influence a part of the urban system relevant to older people's transportation, such as the zoning of land, the approval of housing developments, and the location of bus stops. However, these individual actions are constrained by others in the system. We interpret this complexity with a governance lens. Key messages Efforts to promote mobility in old age should move beyond ‘single solutions to single issues’ approaches toward those that reflect the complexity of cities and the ways that people move within them. For sustained realization of desired outcomes, age-friendly initiatives cannot occur in isolation, but rather must take into account the behaviours and dynamics of the urban system.

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A Study on the Integration of Resilience and Smart City Concepts in Urban Systems

Infrastructures ◽

10.3390/infrastructures6020024 ◽

2021 ◽

Vol 6 (2) ◽

pp. 24

Author(s):

Anastasia Tzioutziou ◽

Yiannis Xenidis

Keyword(s):

Smart City ◽

Research Field ◽

Urban Systems ◽

City Management ◽

Urban Resilience ◽

Continuous Growth ◽

Management And Development ◽

The Many ◽

Development And Management

The continuous growth of cities brings out various concerns for improved development and management of the multifaceted urban systems, including those of resilience and smartness. Despite the many significant efforts in the research field, both notions remain changeable, thus retaining the lack of commonly accepted conceptual and terminological frameworks. The paper’s research goals are to designate the current direct and indirect links in the conceptualizations and research trends of the resilience and smart city frameworks and to prove the potential of the conceptual convergence between them in the context of urban systems. The application of a semi-systematic literature review, including bibliometric evidence and followed by content analysis, has led to the observation that as the resilience discourse opens up to embrace other dimensions, including technology, the smart city research turns its interest to the perspective of urban protection. Therefore, both concepts share the goal for urban sustainability realized through specific capacities and processes and operationalized with the deployment of technology. The paper’s findings suggest that the conceptual and operational foundations of these two concepts could support the emergence of an integrated framework. Such a prospect acknowledges the instrumental role of the smart city approach in the pursuit of urban resilience and unfolds a new model for sustainable city management and development.

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