Resilient Design at the City Scale

Resilient Design at the City Scale DESIGN INVESTIGATIONS

designing for resilient cities means working within interconnected systems

A city encompasses a complex network of systems, from the ecological to the architectural to the political. Our cities are constantly evolving, by choice or by circumstance; what are the factors that allow some cities to thrive over the long term, while others struggle to bounce back from adversity? Designing for resilient cities means working within interconnected systems to create places that can withstand, adapt to, and recover from change.

Cities face a variety of shocks and stressors, and must be able to anticipate and prepare for a range of events. Shocks are fastmoving disruptions such as a natural disaster, pandemic, or civil unrest, while stressors are slower-moving crises such as climate change or a shortage of affordable housing. In the Southeast, challenges include population shifts (both upward and downward), sea level rise, increasingly severe storms, changing economies, and an ongoing reckoning with historical injustices which have led to persistent inequalities.

Population growth in the Southeast is outpacing growth nationwide, and this trend is expected to continue. The influx of companies, residents, and visitors brings significant opportunities to reimagine our built environment for future uses. Civic leaders, architects, urban designers, residents, and other stakeholders can – and must – work together to plan for resilience over the long term.

According to Bloomberg, roughly 2.2 million people moved to the Southeast in the two-year span between 2021 and 2022i.

Reasons for the influx include a mild climate with multi-seasonal recreational opportunities, a lower cost of living than many major metropolitan areas, and a range of attractive options from charming small towns to large urban centers. Major companies are increasingly drawn to the area as well, bringing expanded professional opportunities in industries from technology to automotive engineering to aerospace. Southern states including the Carolinas, Georgia, Tennessee, Florida, and Texas now contribute more to the US GDP than the Northeastii.

As the Southeast continues to grow and evolve, a strategic, multidisciplinary response will help us to design communities which can withstand a variety of challenges, from climaterelated events to economic and cultural shifts. A thriving city relies upon interconnected systems including transportation, zoning, utilities, public services, private development, and natural ecology. A holistic approach to planning and design acknowledges the importance of, and balance between, complex systems in a changing world.

Frameworks for Decision Making at the Urban Scale What do resilient cities look like? To evolve successfully in the face of constant change, our cities must be easily adaptable and designed for flexibility. Robust, redundant infrastructure will be positioned to withstand shocks and stressors. Designing for long-term sustainability will enable a city to meet today’s needs while preserving resources for future generations to do the same.

Connected cities are more equitable cities, allowing everyone equal opportunities and access.

Place-Based Solutions (at Any Scale) The first rule of thumb for any planning and design endeavor is to design with, not for. A successful project is rooted in authentic stakeholder engagement. The project team may begin with civic representatives, urban planners, architects, landscape architects, and an array of engineers, but should also include representation from community members, organizations, and end users who will be impacted by the work.

Each city grapples with different challenges and exists within a unique cultural and geographical climate. The Southeast encompasses extremely diverse landscapes, from coastal plains to piedmont to mountain ranges. The needs of a low-lying coastal city with a significant tourist economy might be very different from the needs of an inland city adapting to a changing employment landscape. Understanding the opportunities and threats facing each city, along with vernacular knowledge and culture, will be critical to developing viable place-based solutions.

According to the U.S. Climate Resilience Toolkit,iii significant risks for the Southeast include extreme heat, flooding, vectorborne diseases, and severe weather events. FEMA’s National Risk Indexiv also offers granular data on climate-related risks at the county level, including social vulnerability and community resilience. Traditional design solutions may offer enduring lessons about designing in harmony with the climate. Examples include the Charleston single house, which maximizes air flow in a warm environment; the rhythm of pedestrian scale “front porch” neighborhoods that encourage community connections; coastal structures elevated well above historic storm surge levels using pilings; or steeply pitched barn roofs designed to shed snow loads in the mountains. In planning for future scenarios, drawing upon both successes and lessons learned can lead to innovative solutions.

Adaptable Design A city is an aggregate of boroughs, neighborhoods, blocks, streets, buildings, rooms, and the circulation corridors and green spaces that bind them together. Adaptive strategies at each level of resolution provide varying degrees of intensity when implemented at the scale of the city. At the urban scale – the public realm – designing for adaptability requires a collaborative mindset of cooperation, conflict resolution, and participation. At the architectural scale – private dwellings, commercial buildings, individual schools, places of worship and healing – designing for adaptability is more focused on the details of building technology, materials, waste, and the economies of real estate. Resilient city design encompasses all scales of intervention.

AT THE URBAN SCALE Master planning for strategic growth and change. Rather than serving as a rigid plan with a linear schedule for implementation, a master plan should be rooted in vision and values, and should serve as a framework of potential uses and long-range goals which can flex with changing needs over time.

Identifying multi-use public spaces. Ideally, everything in the public realm serves more than one purpose. For example, a waterfront park can provide recreational space, feature a music venue, and serve as a city-scale filtration area during a flooding event.

Rethinking streets. Diverse types of mobility might include vehicles, bikes, strollers, walkers, scooters, or trams. Streets designed exclusively for cars might lend themselves to a redesign with different levels for walkers, cyclists, and cars. Overly wide streets might benefit from a “road diet” that provides room for amenities such as tree buffers and sidewalk seating space.

Working with, not against, natural systems. Analyzing natural patterns for movement of water, prevailing winds, wildlife corridors, and other natural elements can guide holistic city planning efforts and cyclical design thinking.

Anticipating changes. Technology, industry, climate, and the economy will continue to change. Designing for maximum flexibility will help cities respond to ongoing changes, including the “unknown unknowns” that can’t be predicted.

Reevaluating zoning ordinances. Traditional zoning defines the uses permitted in each area, which can contribute to problems such as sprawl, lack of affordable housing, or overly restrictive ordinances that dampen innovation. Form-based codes, on the other hand, determine the appropriate scale and form of a building for a particular zone while allowing a broader mix of uses, often leading to better walkability and a thriving mixed-use environment.

AT THE BUILDING SCALE Specifying building envelopes, skins, and structural systems that can react to changing conditions. Designing with, or even creating, dynamic architectural elements allows buildings to adapt to changing ambient conditions with smart building technology. Examples include shading devices or electrochromic glass which automatically adjusts for optimal light conditions.

Planning for modular, reconfigurable building footprints and systems. Planning for future expansion, strategic disassembly, or surgical replacement of systems and components can help buildings grow, shrink, or change with minimal impacts.

Prioritizing flexible floor plates and building layouts. Flexible column grids with demountable walls allow for easy reconfiguration to accommodate changing functions and evolving needs over time.

Designing for layered building systems and separation of assemblies. Designers should assume that building components will need to be maintained, repaired, replaced, and eventually disassembled. Ease of access and the use of mechanical fasteners rather than adhesives will facilitate repair and replacement.

Selecting flexible furniture systems. Incorporating adaptable furnishings and other building products to define spaces while minimizing hard construction will allow for easy reconfiguration.

Designing the core and structure of commercial buildings for maximum flexibility. Commercial uses may shift over time along with changing ways of working. Designing to allow future conversion would allow an office to shift to a future retail or residential space, or make it easy to transition from a single-tenant space to smaller offices for more tenants with shared amenities at the core.

Updating zoning regulations. Cities can examine existing codes and look for adjustments which can make it easier to change a building’s function as needs evolve.

Renewable energy sources such as solar and wind power can reduce pressure on the traditional power grid at the building, neighborhood, or city scale, and can potentially help cities return to normalcy faster in the event of a prolonged power outage.

Robust, Redundant Infrastructure The health and safety of a city’s residents depend on the utilities and services we often take for granted: power, water, transportation, solid waste removal, communications infrastructure, and emergency services. Long before a crisis, civic leaders and representatives of all impacted departments should develop plans to safeguard infrastructure in a range of scenarios. Critical infrastructure should be durable, secure, strategically located, and accessible. Emergency operations centers, hospitals, and shelters should be located on high ground with multiple access points. Redundant systems for food, water, power, transportation, communications, and healthcare, potentially operating in a “hub and spoke” model, can allow one facility to remain operational if others are taken offline.

Investments in resilient infrastructure support a better quality of life for communities over the long term, not just in a disaster. As cities grow, long-range planning for sewer, recycling, composting, and landfill capacity will be increasingly important. Renewable energy sources such as solar and wind power can reduce pressure on the traditional power grid at the building, neighborhood, or city scale, and can potentially help cities return to normalcy faster in the event of a prolonged power outage.

Resilient transportation systems support a variety of modalities – vehicular, pedestrian, bike, and public transit options – safely and efficiently. Planning transportation systems which can adapt over the long term goes hand-in-hand with strategic master planning for growth and change. In identifying targeted nodes of density and urban-scale development, city planners can direct resources where they will be most needed, lay the foundation for transit-oriented development as neighborhoods grow, and pave the way for a more sustainable, more connected future.

Long-Term Sustainability Designing for a sustainable, resilient future means managing our resources wisely as we plan for change. Reducing the amount of carbon released in the atmosphere is imperative for mitigating the effects of climate change, and will require a shift in our thinking and our systems. Cities are poised to make significant positive impacts by enshrining sustainable values in building codes at the urban scale.

Adopting stringent energy codes, electrifying systems, and investing in renewable energy sources will help to reduce operational carbon. Incentivizing adaptive reuse of existing buildings for new uses will help to reduce the embodied carbon required for new construction. Cities can also make it easier for people to reduce their vehicle miles traveled (VMT) with attractive public transit options, transit-oriented development, and codes that encourage pedestrian and bike activity.

Preserving and creating green spaces provides a host of benefits: natural infiltration of stormwater, more places for wellness and connection, wildlife habitat, and cooler urban cores. Cities can maintain green spaces by restricting development on sensitive sites such as wetlands or greenfields, and incentivizing urban infill and adaptive reuse projects. Codes can also include density bonuses or other incentives for minimizing building footprints to create or maintain public green space on individual sites.

Southeastern cities in particular will need robust strategies for managing water and heat as storms become more intense, coastal and inland flooding increases, and temperatures rise.v A deep understanding of local and regional hydrological systems will help planners and engineers design for water systems over the long term, including navigating extreme rainfall volumes, droughts, or sea level rise. Restoration of former wetlands, dedicated buffer zones for high water events, requirements for low-impact development, and contingency plans for flooding are all important strategies.

Any new development will need to come with requirements for managing water onsite and safeguarding existing waterways.

Managing extreme heat will require cities to reduce urban heat islands and re-think areas with expanses of pavement. Sidewalk and parking lot plantings for strategic shade and evaporative cooling will need to target the most at-risk areas, and public green spaces can mitigate temperatures as well. Cities may consider grant programs for strategic retrofits for public, commercial, and residential buildings to encourage strategies such as white or vegetated roofs, envelope improvements, or more efficient HVAC equipment such as heat pumps. Cities will also need to consider cooling centers for those most at risk during heat waves, and consider restructuring workdays to avoid dangerous heat for workers who must be outdoors.

Equal Opportunities & Access The ability of a city to withstand, adapt to, and recover from change also depends upon the ability of a diverse citizenry to participate equally in opportunities. Those at the lowest income levels are often disproportionately impacted by a crisis, so addressing inequalities proactively can help all residents prepare for and weather change.

Building opportunities for authentic connections at the city scale can also strengthen community ties and reinforce support networks.

Economic development. People at all income levels contribute to thriving places, and cities should support a broad range of options for employment.

Pop-up stores, incubator spaces, and food trucks/food halls boost streetlevel activity while providing start-up spaces for small businesses. Ideally, local educational opportunities work in conjunction with businesses to align training opportunities with emerging industries. City leaders should evaluate zoning ordinances and targeted zones for investment for strategic and equitable resource allocation, and should be mindful of preserving traditional neighborhood businesses in areas that may be rapidly changing.

Affordable housing. A healthy city requires layers of affordable housing for low income, workforce, middle income, and market rate housing. Cities may need to re-think existing codes and become proactive about inclusionary zoning, neighborhood-scale multifamily options such as duplexes and triplexes, or accessory dwelling units (ADUs) to provide a full range of options.

In a literal economic sense, “equity” refers to homes and wealth building, so building a mixed-income neighborhood with a wide variety of price points allows people to stay in their neighborhood and invest in relationships as they grow in income or family size and seek different types of housing nearby.

Connectivity. Shared public spaces are critical to belonging and engagement.

These can be multiuse green spaces which serve a variety of functions in which people have opportunities to interact with a space and with each other.

Public parks should ideally be programmed; one example would be chess tables to facilitate activity and connection. Transportation is another key requirement for connectivity. A robust transportation system (public transit, bike lanes, greenways, pedestrian and vehicular routes) should link walkable neighborhoods and easy-to-access amenities.

Universal Design Principlesvi 1. Equitable Use (useful to people with diverse abilities) 2. Flexibility in Use (accommodates a wide range of preferences and abilities) 3. Simple and Intuitive Use (easy to understand regardless of language skills, knowledge, or attention span) 4. Perceptible Information (communicates necessary information effectively) 5. Tolerance for Error (minimizes consequences for accidental actions) 6. Low Physical Effort (can be used with a minimum of fatigue) 7. Size and Space for Approach and Use (can be used regardless of size, posture, or mobility)

Accessibility. People come with a wide range of physical abilities, and public spaces should be designed so that everyone can use them. Abovecode-minimum designs can make the difference between making it through a space and enjoying the experience of being there. The principles of universal design remind us that good design benefits all types of people: families using strollers, multigenerational groups, those permanently using wheelchairs or those temporarily using crutches.

Inclusion. Beyond being able to use a space, everyone should also feel welcome in a space. The built environment of a city should convey a shared identity through public art, murals, programming, and storytelling that celebrates the community’s values, culture, and history.

Justice. Designing for a resilient city will, in many cases, require addressing harm from previous interventions. Historic injustices such as redlining or bisecting historic neighborhoods with highways have impacted many cities in the Southeast, leading to persistent inequalities in access, connectivity, and opportunity. Mitigating these problems may require redesign and reinvestment to knit neighborhoods back into the urban fabric, distribute resources equitably, and provide equal access to opportunities for all.

Civic engagement. Cities need to provide places for gathering, celebrating, voting, and other civic activities. As traditional places for community engagement ebb and flow over time, thriving communities will need new types of places for engagement, conversation, navigating difficult issues, and contextualizing layers of history in a shared public realm, and cities can be proactive about creating these places of overlap.

Designing a Resilient Future Though we can rarely predict how a crisis will unfold, we do have the tools to anticipate a variety of scenarios and design for the most positive outcomes. In the event of a natural disaster or other emergency, resilient cities will be better prepared to weather difficult times, adapt to change, and recover as quickly as possible. Cities that prioritize adaptability, invest in robust infrastructure, work towards long-term sustainability, and foster a culture of equity will be best prepared to withstand both shocks and stressors in a changing world.

designing for resilient cities means working through interconnected systems

Works Cited Sasso, Michael and Tanzi, Alexandre. June 29, 2023. “A $100 Billion Wealth Migration Tilts US Economy’s Center of Gravity South. https://www.bloomberg.com/news/ features/2023-06-29/millions-move-to-the-south-as-us-economy-favors-its-wealth-jobopportunities#xj4y7vzkg i

Sasso, Michael and Tanzi, Alexandre. June 29, 2023. “A $100 Billion Wealth Migration Tilts US Economy’s Center of Gravity South. https://www.bloomberg.com/news/ features/2023-06-29/millions-move-to-the-south-as-us-economy-favors-its-wealth-jobopportunities#xj4y7vzkg ii

U.S. Climate Resilience Toolkit. Modified June 28, 2021. “Southeast.” https://toolkit. climate.gov/regions/southeast . iii

FEMA. N.d. “The National Risk Index.” Accessed October 17, 2023. National Risk Index | FEMA.gov . iv

EPA. N.d. “Climate Impacts in the Southeast.” Accessed October 24, 2023. https://19january2017snapshot.epa.gov/climate-impacts/climate-impacts-southeast_. html v

National Disability Authority (NDA). N.d. “The 7 Principles.” Accessed October 24, 2023. https://universaldesign.ie/what-is-universal-design/the-7-principles/. vi