How can green infrastructure and regenerative asset management build resilient cities?

Infrastructure as we know it serves a purpose of providing a physical space for the interactions we perform in an urban setting: offices, schools, hospitals, roads, bridges, etc. Green infrastructure (GI) also contemplates these buildings and physical elements while incorporating natural assets (such as native vegetation, wetlands and parks), enhanced/hybrid assets (such as green roofs, bioswales and rain gardens) and engineered assets (such as permeable pavement, perforated pipes, infiltration trenches and cisterns). Respecting the flora, fauna and weather cycles, GI is a way to integrate infrastructure into the natural setting.

Green infrastructure’s natural vegetative systems and green technologies can be applied on multiple scales. Collectively, they provide society with a wide range of economic, environmental, health and social benefits and services.

While GI has been a recognised concept and discipline for decades, and the design and construction of GI assets are advancing, the field is still evolving. This means that terminology, definitions and types of assets and solutions can vary between different areas.

Many municipalities across Canada have implemented GI assets, but planning is often informal and opportunistic. There is a lack of guidelines and standardised approaches for managing GI assets throughout their life cycle. Integrating GI assets into traditional asset management systems is an emerging practice and municipalities with established GI asset management programs are uncommon.

The vast majority of asset management ownership and governance for conventional infrastructure assets follows a single ownership model, where all assets of a particular type or class are the sole responsibility of one division or branch. Municipal asset management systems are typically configured for this single-owner setup, with data management, GIS, reporting, financing and risk frameworks all designed accordingly.

However, GI assets are unique in that they comprise a combination of component assets owned and maintained by different divisions and branches. That’s why ownership, responsibility and accountability must be clearly defined.

While the advantages of GI are increasingly acknowledged, municipalities aiming to initiate or broaden their programs continue to face significant challenges including resource constraints, lack of data clarity, strategic and operational hurdles, measurement and evaluation shortcomings, stakeholder coordination, inconsistent planning and even cultural paradigm shifts. A robust GI asset management program can help overcome these challenges.

GI can be implemented at a variety of scales, from the lot-level to neighbourhood or city wide, to the regional or watershed scale. These individual assets combine to create living GI networks, providing a wide range of environmental, economic, physical, psychological and social benefits, both directly and indirectly, while offering valuable services to communities.

Healthy ecosystems contribute to a municipality or region’s overall resilience to environmental extremes. Used in conjunction with traditional infrastructure, GI can result in deferred or reduced maintenance costs and can extend the remaining service life of grey infrastructure assets, reducing functional burden and providing long-term cost savings. Ecosystem services can also support other economic activities such as recreation, sport and ecotourism. GI also supports both climate change mitigation and adaptation, promoting overall climate resilience.

It is important to understand that GI is infrastructure and should be recognised and treated as such — therefore the same language and terminology should be used when talking about traditional grey infrastructure or GI.

Incorporating GI into asset management programs, plans and processes supports holistic decision-making for infrastructure management. The ability to directly compare conventional infrastructure and GI is essential as it empowers municipalities and their leaders to make decisions that are defendable and transparent.

Regenerative asset management is a holistic approach that considers the interconnectedness of natural and human-made systems. With GI as one of its key tenets, it embeds sustainability and resilience principles into infrastructure asset management thinking and approaches. It represents a step beyond traditional asset management to incorporate sustainability and resilience goals by integrating built environments with nature. GHD believes regenerative asset management creates a positive impact on the environment, society and economies through the transformation of service provision and manufacturing.

GI assets are often associated with water/stormwater management, mitigating localised flooding events, managing stormwater runoff, addressing stormwater retention, responding to rainwater on-site, improving water quality, cleaning and cooling the air, absorbing GHG emissions, all the while providing space for recreation, enhancing aesthetics and supplying habitats for birds and pollinators and more natural fauna.