Assessing the role of active travel routes in enhancing blue-green infrastructure connectivity in Huelva City

Abstract

The rapid urbanisation and increased climate variability present significant challenges to urban infrastructures, necessitating integrated and sustainable solutions. This thesis investigates the integration of Blue-Green Infrastructure (BGI) and Active Travel Routes (ATRs) in Huelva, Spain, to enhance urban resilience by optimising hydrological connectivity. BGI including parks, water bodies, and wetlands, play an integral role in biodiversity support, stormwater management, and climate change mitigation. ATRs, such as cycle paths and pedestrian walkways, promote sustainable transportation, reduce greenhouse gas emissions and improve public health. The integration of BGI and ATRs can provide a holistic solution to contemporary urban challenges, including pollution, flooding, and climate change. A detailed assessment of the distribution and co-benefit of existing BGI and ATRs was conducted, and optimal ATRs were identified to enhance hydrological connectivity using GIS-based mapping and cost-raster analysis. The study found that Huelva has a moderate presence of parks and pocket parks concentrated in central areas, offering considerable ecological and hydrological benefits. Among the BGI in Huelva, parks provide the highest ecological benefits, while wetlands provide the highest hydrological benefits. However, existing BGI show higher ecological benefit values lacking blue features highlighting the need for improved hydrological considerations. Optimised ATRs designed for hydrological connectivity significantly increase BGI connectivity up to four times for optimal core connections and eleven times for optimal complementary connections compared to the existing plan. These optimised routes could facilitate effective water diversion and retention, mitigating flood risks and improving water management. The study presented a conceptual design of an exemplary site by enhancing the quality of available urban spaces while identifying priority sites for equipping and retrofitting buildings for rainwater management and vegetation. The findings suggest the necessity of a holistic approach in urban planning that incorporates BGI and ATRs integration. The study sheds light on challenges such as data availability, consistency, and public engagement recommending collaboration in city planning among different departments to ensure sustainable urban development. The research lays the foundation for future studies and practical applications with a novel methodology integrating blue spots and streams into existing BGI and connecting them using ATRs. Future research should delve deeper into the impacts of integrated ATRs and BGI elements, exploring the relationship between accessibility, usability, and sustainable transportation. By embracing the integrated approach, cities can significantly enhance their resilience to environmental challenges and improve the quality of life of the residents. In summary, the thesis provides a comprehensive framework for the integration of BGI with ATRs, offering valuable insights and practical recommendations for urban planners and policymakers of all disciplines involved in urban planning and development to foster resilient, sustainable and inter-connected urban environments.