4.1. Portland: The Portland Plan
In 2012, Portland developed the Portland Plan, which was the product of a wide coalition of public and private actors and non-profit organizations. With a core set of priorities that includes prosperity, education, health and equity, the Portland Plan set long-term and short-term sub-strategies for the next 15 years. In the framework of equity, the Plan focuses on “identifying disparities to close the gaps, delivering equitable public services and engaging meaningfully with the community” [
57]. The plan is articulated around three integrated strategies that include an overall goal and supporting objectives, guiding long-term policies and a five-year action plan (2012–17). The policies and actions in each strategy are grouped into strategy elements while actions and policies in each strategy element share common themes. The plan is implemented through the City’s Comprehensive Plan Update, revisions to the City’s budget, new operating practices, legislative advocacy and intergovernmental agreements. Since it was launched, the plan provided a structure for aligning budgets and projects across numerous public agencies and guiding policies up to the year 2035.
In short, the first strategy “Thriving Educated Youth” focuses on creating a culture of high expectations and achievement for all Portland youth, neighborhoods and communities that are supportive to youth, as well as facilities and programs that meet contemporary challenges and opportunities. The second strategy “Economic Prosperity and Affordability”, place emphasis on boosting urban innovation, job growth and employment opportunities, access to affordable housing and neighborhood business vitality. Finally, the “Healthy Connected Cities” strategy refers to the safety and health of citizens, the regeneration of neighborhood centers and the connection between people, places, water and wildlife [
57].
The notion of the 20-min neighborhood is integrated in the “complete neighborhood” (CN) concept that falls under the goal of “Healthy Connected Cities”. Moreover, several features of the CN are interwoven into other strategies as a way to support youth success, provide access to affordable housing, promote community-driven neighborhood economic development and spur commercial activity in underserved neighborhoods. According to the plan, the term “complete neighborhood” refers to a neighborhood where one has “safe and convenient access to the goods and services needed in daily life. This includes a variety of housing options, grocery stores and other commercial services, quality public schools, public open spaces and recreational facilities, affordable active transportation options and civic amenities. An important element of a complete neighborhood is that it is built at a walkable and bikeable human scale and meets the needs of people of all ages and abilities (
Figure 1).
For the application of the CN model a 20-min neighborhood index was developed in order to measure accessibility to a variety of amenities, products and services. If a neighborhood achieves a score of 70 or higher, on a scale of zero to 100, it is considered a relatively complete neighborhood (
Figure 1). The goal of the strategy is that 90% of the residents to be able to walk or cycle and cover all their needs, except work, within 20 min [
58]. In the calculation of the index topographical and geographical elements such as rivers and steep slopes, highways, crossroads and other natural obstacles for pedestrian movement are taken into account. It also records factors that improve the walking experience such as the presence of sidewalks, signage, diversity of routes and connections, access to high quality and frequent public transport, and proximity to core areas of services and activities [
57].
CNs hold a central place in the plan as a way to promote urban environments that enhance economic vitality, inclusion, safety, health and emergency preparedness, through multiple objectives and actions. They provide a variety of urban services and public facilities in a relative dense urban environment with multiple active mobility options and in proximity to a transport node. The community centers located in each CN aim at supporting a wide range of daily basic services, at local scale.
As part of the Plan’s goal for economic development and financial resilience, CNs are intended to create a favorable environment for the development of “home” and neighborhood-based businesses that offer a variety of opportunities to enhance local employment, minority entrepreneurship, wage growth and household self-sufficiency [
57]. Moreover, through the economic and prosperity strategy, CNs are key attributes for supplying affordable housing and creating equal opportunities in homeownership. CNs are also part of city’s network of hubs and connections and are considered as high opportunity areas, with improved physical accessibility and visitability, to best meet the needs for a growing and socio-economically diverse population. This includes supply of quality affordable housing of different unit types and prices, catered to low-income households, including seniors on fixed incomes and people with disabilities. The plan’s measures and actions prioritize the transformation of neglected and low-income neighborhoods and promote a housing policy that is sensitive to income inequalities. It also proposes measures to mitigate gentrification phenomena by increasing the ability of low-income households to access homeownership opportunities, promoting public investment in housing and designing housing in and around neighborhood centers and near transit—at a variety of sizes and cost ranges.
For transport there are provisions for multiple mobility options that enables affordable transportation to and from work, in and outside city limits. Multimodality is high priority, including all options that enhance active mobility. A hierarchical system of “civic corridors” and “neighborhood greenways” form the spine for a nexus for multiple urban-social functions. Civic corridors are transit corridors connecting CNs with each other, but also with the city center. Adequate access to key urban functions and proximity to major transport hubs is ensured through a network of “neighborhood greenways” that includes sidewalks, bicycle paths, greenway trails and bike-friendly green streets. It is worth noting that the strategy promotes the conversion of roads to more accessible and pedestrian-friendly activity corridors, with improved sidewalks, crossings and other pedestrian friendly facilities as a way to ensure safety. It also acknowledges that there is room for improvement for the bus system.
A strong aspect of the plan is the promotion of walking or cycling as a way to fight obesity, cardiorespiratory and chronic diseases. The plan envisages an accessible and multi-functional hierarchical system of parks, green corridors and open spaces that contributes to a healthy environment and a lifestyle that favors walking. The system of green areas is intended to cater all ages and abilities including the elderly and people with mobility issues. Side benefits include the enhancement of natural habitats and improvement of neighborhood microclimate. Moreover, provisions for alternative transport options that discourage the car usage contributes to the reduction of carbon dioxide emissions and thus respiratory diseases. Finally, amid the COVID-19 crisis more than 90 miles of busy roads have been turned into green corridors where dense tree plantation offers shade and traffic decongestion at local and citywide level [
4]. This measure was intended to achieve social distancing by avoiding car usage and gathering of citizens indoors [
4,
59]. Moreover, implementation procedures for CM were speeded up so that 90% of citizens live in complete neighborhoods [
4].
Rooted to the adopted 2009 Climate Action Plan, the network of habitat connections, greenways, parks and open space is also considered as the spine for the development of green infrastructure systems. Green and grey functions such as managing stormwater, improving water quality, reducing flooding risk and providing wildlife and pollinator habitat are realized through a green infrastructure system. It is worth noting that with the advent of the Coronavirus in 2020, the city set new priorities for long-term green infrastructure projects [
4].
Access to healthy and affordable food holds a key role in the strategy, where residents of any nationality or color should have access to fresh food from small local businesses in their neighborhood. According to the Plan, in 2012 only 30% of citizens had access to a grocery store within half a mile. Hence, it proposes alternative methods for accessing fresh and culturally relevant food. Specifically, through the “Healthy Retail Initiative” there is an effort to retain and recruit a variety of healthy food sources, create community gardens and cooperatives of community agriculture.
Engaging community in the CN’s planning process and strengthening equity in decision-making is constant throughout the plan. Transparency, building capacity to participate, and providing resources for the early engagement of citizens is heavily promoted as a way to build a sense of community ownership and achieve plan’s acceptability and social legitimacy. Initiatives on building community, organizing community’s capacity and engaging people in shared governance are targeted mainly at the under-represented and underserved communities. Moreover, building relationships with public and private sector partners is considered necessary with key goals being mutual learning, exchange of knowledge and pursuit of complementary work to advance equity in decision-making.
As for the implementation of the Plan, the principles of the sub strategy “Healthy Connected City” are incorporated into the City’s Comprehensive Plan to coordinate policies, land use planning and investment decisions. Furthermore, Portland’s neighborhood centers and connections are part of the regional land use, transportation, growth management and open space system, which is coordinated by Portland’s Metro. Metro also plays a significant role in facilitating a regional strategy to promote reinvesting in existing communities.
Overall, the plan promotes neighborhood self-sufficiency, by localizing basic urban functions that include health, education, childcare, retail, recreation and fresh food production. Proximity to urban functions is supported by a hierarchical system of transport axes that includes “Civic corridors” and “Neighborhood greenways”. Nevertheless, application of the CN model implies a quite high degree of localization of activities that is not currently in place. It is not clear how the required market range and threshold populations for these activities will be ensured in a medium urban density environment. The Plan also strives for equitable access to jobs with local employment opportunities within CNs. To this end, “Complete Neighborhoods” are part of a larger network of neighborhood centers that are connected to the city center and other major employment centers.
Table 2 summarizes the overall evaluation of the Portland Plan based on the three pillars.
4.2. Melbourne: Plan Melbourne 2017–2050
Plan Melbourne 2017–2050 is a long-term strategy that seeks to accommodate the challenges posed by an ever-growing population and employment. These include providing affordable and accessible housing, ensuring adequate number and diversity of jobs, containment of urban sprawl, accessibility and adequacy of transport, mitigation of green-house emissions, and adaptation to climate change [
60]. The Plan is accompanied by a separate five-year implementation document, with particular focus on the short-term actions and the governance framework required for its successful implementation.
Plan Melbourne’s vision for a global city of “continuous opportunity and choice” is achieved through nine principles that include: (i) preserving the distinct character of the city, (ii) being an internationally networked and competitive city, (iii) being the focus of a network of clusters, centres, precincts and gateways, (iv) protecting biodiversity and natural assets, (v) promoting social mobility to enhance social cohesion, (vii) ensuring that neighborhoods and suburbs are diverse, inclusive, safe and heathy, (viii) building effective governance, strong leadership and collaborative partnerships and finally (vx) promoting local living in the form of 20 min neighborhoods. The strategy is articulated on 7 outcomes or strategies, 90 policies and 32 directions.
The notion of “20-min neighborhoods” is embedded in one of strategies that aims at a city of inclusive, vibrant and healthy neighborhoods. A 20-min neighborhood is defined as “giving people the ability to meet most of their everyday needs within a 20-min walk, cycle or local public transport trip of their home” and is intended to “help improve health and wellbeing, reduce travel costs and traffic congestion and reduce vehicle emissions” [
60]. They are considered the means to build city wide social sustainability by promoting the well-being of its citizen through local living. According to the Plan they represent the most appropriate scale and structural element to meet basic citizen needs such as participation in activities and access to services and social infrastructure. They provide a wide array of urban and social services locally and intend to promote prosperity, health (mental and physical), social inclusion, sense of belonging, participation, choice, adaptability and employment opportunities.
In particular “20-min neighborhoods” include a series of 17 urban and social functions that should be accomplished within their jurisdictions.
Figure 2 provides an overview of the proposed functions. A critical structural feature of the 20 min neighborhoods is the “neighborhood activity centre” (NAC), which is the focal point of the neighborhood (the Plan refers to them as high streets or specialized streets) and provide a variety of urban functions such as recreation, retail, services, education etc. NACs are also places of work and have the potential to be community hubs, creating an environment for social interaction and community participation. The Plan does not make specific references to the physical size of the neighborhood though it is implied that is defined by a 20-min journey of walking, cycling or using local public transport from home. According to Kagan, given the average walking time of a healthy adult and taking into account waiting at junctions and meandering routes, the distance that someone can cover in 20 min is about 800 m or half a mile [
58]. Research in regard to NACs physical demarcation suggests that there are several evidence-based metrics required to inform such process, including the surrounding built environment features, placing emphasis on density features [
61].
It is important to note that Melbourne’s urban development pattern was shaped by car-oriented policies. As such it consists of a low-density zonal type of development with separation of basic urban functions such as housing, working, entertainment, shopping etc. Hence, critical determinants in achieving cohesive NACs are high density development and diversity of uses in order to be able to support a variety of urban functions and optimize the value of infrastructure. Despite the fact that the issue of density is not explicitly mentioned in the principles of “20-min neighborhoods”, it is a major concern throughout the plan. The Plan emphasizes the importance of residential density and proposes raising the standards of higher-density housing. This applies to the central city, the inner and outer suburbs. Moreover, it recognizes infill and densification opportunities through renewal strategies in residential areas, activity centers, employment and innovation clusters and railway stations located on the principal public transport network. Finally, the Plan promotes the development of a diverse mix of uses locally (in NACs), that includes shops, education facilities, places of entertainment, sports and other recreational and social activities.
Diversity is also promoted for mobility choices which include active mobility options like walking or cycling in combination with public transport. According to the Plan NACs are perceived as highly walkable areas. Walking or cycling in these areas is encouraged using appropriate design principles and infrastructure, mainly for local routes. Travel safety is also addressed by proposing several measures that ensure pedestrians’ and bikers’ safety i.e., bicycle lanes, school drop-off zones etc. Moreover, combing micro mobility choices with public transport aims to provide access to other activity and employment centers citywide. The Plan proposes a Principal Public Transport Network (PPTN) where high-quality public transport services are or will be provided. Hence, it is crucial to channel development of high diversity and density on and around the PPTN. Nevertheless, NACs are not explicitly linked to PPTN due to Melbourne’s low-density urban environments. In addition, given Melbourne’s sprawled type of development, public transit can be viable only in certain areas [
61]. Studies for the city of Melbourne advocate that providing local public transport service in support of the NACs is quite tricky for the inner and especially for the outer suburban parts where the greatest need exists with respect to achieving a 20-min city. The use of demand responsive and flexible transit service is suggested as a viable solution, especially for the outer suburbs [
62]. Therefore, local public bus service is considered as the primary mass transit option since it could offer adequate service level that can be economically justified.
Managing and supplying new housing in the right locations to meet population growth and create a sustainable city, is another major challenge for Melbourne. NACs and its surroundings are designated as places where an increased percentage of new housing is channeled. Not all NACs are appropriate, therefore there is a priority plan depending on the proximity to existing services, jobs and public transport. As built environment features surrounding NACs must reach certain density levels, a minimum of 25 dwellings per hectare is suggested [
63,
64]. Regarding the issue of affordable housing, the Plan pursues equal accessibility opportunities to all income and social groups, seeking to reduce inequalities within the city [
3,
59,
63].
Promoting healthy lifestyles is achieved through increased physical activity opportunities and development of a network of green spaces. In fact, the plan aspires to increase walkability options with the full pedestrianization of NACs and the use of pedestrian-friendly infrastructure with access for all ages and people with disabilities [
58,
65]. In addition, green areas provide more places for rest and recreation, as well as space for social interaction and connection with the natural environment. In this network of accessible and high quality local open spaces, other types of spaces, such as schoolyards, can be included to offer space for other activities i.e., sports and vice versa. Community landscaping, revegetation and gardening is part of the Plan’s intention to provide opportunities for sharing skills and knowledge, increasing social interaction and community partnerships and producing local food for personal consumption or for sale at local markets. Citizen’s involvement in such activities is a prerequisite to increase awareness of the value of open public space. Amid COVID-19 crisis it was decided that a large amount of plant species (approximately 150,000) would be planted, and new habitats were proposed as a way to stimulate biodiversity and create new low skilled jobs [
4].
Special emphasis is given to the provision of social infrastructure locally, as a way to combat car-dependent travel patterns, contributing the most to the realization of the 20-min neighborhood model. Proximity to basic social infrastructure includes schools, kindergartens, early years centres, parks and playgrounds. For the accommodation of a variety of social needs the Plan proposes the use of spaces in a temporal, flexible and adaptive fashion as well as co-location of complementary activities, in order to maximize localization of educational, health and recreational urban functions.
As for the implementation of the plan, Plan Melbourne is a quite mature strategy and has gone through pilot implementation projects in three neighborhoods involving local government, stakeholders and the Resilient Melbourne office. Results highlighted the significance of “bottom-up” approaches and co-planning practices as a way to acknowledge the real local problems and acquire long-term commitment of local communities to the plan.
Overall, 20-min neighborhood is promoted as a new urban development model in order to contain sprawl and create diverse urban environments and housing opportunities. The plan proposes a network of neighborhoods with a certain degree of self-sufficiency, by localizing basic urban functions that mainly include education, childcare, retail, recreation and fresh food production. Application of the 20-min city model implies a moderate localization of basic public functions and their assorted facilities that is not currently in place. However, due to the sprawled urban development patterns and the lack of appropriate transit options, NACs could present different proximity opportunities and realization possibilities. Densifying urban environments in the inner and especially the outer suburbs is probably the greatest challenge for the implementation of the NAC scheme. Moreover, it is quite clear that not all NACs have direct access to quality public transport, therefore it is imperative to facilitate such access as a way to connect people to jobs and higher order services. Otherwise, there is a high possibility that NACs would function more as “pedestrianized islands” in an urban sprawl ocean, rather than proximity cores to urban functions.
Methodologically speaking the Plan does not specify how to measure or define the 20 min radius probably due to the variety of existing housing and activity densities citywide. This implies the need for a methodology that would take into account the different types of development, especially in the inner and outer suburbs. Finally, the Plan does not identify the standard urban functions and associated infrastructure facilities that are localized in each neighborhood. This presents a weakness in terms of evaluating the state of existing neighborhood centers that can function as NACs and the associated improvements.
Table 3 summarizes the overall evaluation of the Melbourne Plan based on the three pillars.
4.3. Paris: Paris en Commun
The Paris En Commun strategy visions a great Paris without borders and increased community involvement. It is rooted in the Paris Climate action plan, the flagship of Mayor Hidalgo’s re-election campaign in 2020, addressing climate change challenges with the revival of Paris’s neighborhoods. In the context of the implementation of the plan, various policies have been adopted with emphasis on reducing car dominance, regaining space from cars, increasing tree canopy and enhancing pedestrian mobility [
7,
66]. One of the notable elements of this strategy is the importance it gives to the participation of citizens in visioning and implementing the plan, as evidenced by the funds that have been allocated for conducting participatory planning processes. Finally, the strategy most recently acquired new attention as a post COVID-19 recovery strategy, reintroducing the concept of the quarter-hour city [
4,
66].
The vision of Paris En Commun strives for a carbon-free economy and a healthy life for its citizens [
67]. It concerns the area of Paris that is confined within the ring road, aka peripherique. The four axes of the strategy include the implementation of ecological measures, solidarity-centered ecological transformation, hyper-proximity and the commitment of citizens to the strategy [
68]. The 15-min concept falls under the hyper proximity axis, as an attempt to create a neighborhood centered city where all inhabitants can cover most of their needs with 15 min, walking or biking, from their place of residence [
7,
68]. The philosophy of quarter-hour city is based on 4 principles: proximity, diversity, density and ubiquity, where neighborhood development must cover six primary social functions: housing, employment, shopping, health care, education and entertainment (
Figure 3a) [
69].
The strategy mentions that the quarter-hour city aims at providing hyper-local self-sufficient arrondissements that will ensure “….
dwelling in dignity, working in proper conditions, [being able to gain] provisions, well-being, education and leisure” [
58]. Since high building density is already a given for Paris, the strategy focuses on the mix of uses including housing with shops, entertainment with medical centers and offices with educational buildings [
7,
58]. Moreover, the quarter-hour city envisages transformative public and semi-public spaces having multiple properties such as schoolyards being able to be converted into sports venues or simply cool places where residents can use during summer nights, weekends or during school holidays. A network of “citizen kiosks” staffed by city employees operate as central multifunctional nodes of communication, exchange of information and service of neighborhood residents. Functions may include simple things like drop off and pick-up keys, join a local club, exchange and reuse of products in application of the circular economy practices, as well as the development of voluntary actions such as supporting sensitive community groups.
The notion of localizing services and functions is evident throughout the plan. Initiatives such as “eat and buy local” promote the consumption of products that have been produced in the “basin” of Paris. In fact, the strategy proposes the creation of cooperatives like the “Agri-Paris” which acquires fresh food and other products from local producers and distributes them quickly and directly to the residents and neighborhood markets of Paris. In addition, small businesses “made in Paris” are also encouraged to enhance development of local entrepreneurship [
7,
68,
69]. Self-sufficiency of households and the neighborhood is also promoted through special programs for improving literacy and unemployment rates. Specific training programs, second chance schools and flexible facilities such as babysitting, aim at helping low-income residents to prepare for local jobs i.e., in circular economy, reuse and item repair, accounting etc.
The quarter-hour city is intended to be a favorable environment for localizing job opportunities and enhance local employment. In fact, in the C40 Mayors’ agenda for the green and fair recovery of the planet by COVID-19, there are several references to enhance remote working and promote the co-location of companies and “relocation” of workplace within the neighborhoods [
4]. This of course implies a great flexibility in terms of opening hours of several local services as well as flexibility in the usage of space itself.
Given that the city of Paris has a well-developed transit system and adequate urban density for a highly walkable environment, the strategy focused on bringing activities to the neighborhoods. Thus, it prioritizes the pedestrianization of large parts of the city along with alternative active mobility options. Neighborhoods in and around the centre of Paris are suggested to be inaccessible to the car, with the exception for the disabled, residents, shopkeepers, taxis, electric buses and emergency vehicles. It also intends to create “children’s roads” next to school units where traffic is banned during the school opening and closing hours [
54]. An additional plan of 300 million euros already in working progress proposes an integrated network of bike lanes, pedestrian and bike friendly roads and green routes (
Figure 3b). The plan aims to serve most of the mobility needs within the peripherique and change mobility habits in the long run. Specifically, the plan aims to increase, by 2024, the network of bike lanes by removing 60,000 parking spots while each road will have a bike lane. Other measures for changing city’s mobility culture include co-boarding, common means of transport (“transports en commun”), electric buses, skates, and extension of operating hours of public transportation (bus and metro). Part of this network are the recently pedestrianized highways that run through the centre at either side of the River Seine. Finally, amid COVID-19 the city installed a regime of “corona cycleways” to alleviate transit crowding and discourage the use of car for commuting purposes. Recent images from the city show an almost Copenhagen-like renaissance of urban bicycling [
58].
Providing inclusive and diverse housing is probably the greatest challenge for the quarter hour city. In particular the Resilient Plan for Paris mentions that over the next 30 years, the city will continue to accommodate new residents, with an additional 200,000 Parisians expected between now (2018) and 2050. On the other hand, there has been a decline in housing accessibility and affordability due to gentrification and real estate speculation. To cope with the housing shortage the strategy aspires to increase its housing supply by having 30% of its housing stock in the public domain until 2030, and ideally to increase the share in high end districts. Furthermore, tax incentives related to vacant dwellings and second homes intend to put dwellings back on the market. Transformation of office space into housing is also considered while co living is promoted as a way to reduce housing costs and create social links between generations [
70].
In the context of mitigating the effects of climate change and reducing air pollution the strategy aims at a greener city. Greening is also related to the preservation of biodiversity within the city in an effort to enhance local habitats and biodiversity. Thus, a network of green corridors, new urban forests, short walking routes, large artificial plantation vessels and new parks are proposed. As for the building stock, there are a variety of measures concerning reduction of energy consumption, which include installing solar panels, planted roofs, rainwater harvesting facilities etc. Composting, recycling and waste separation at local level, as well as zero garbage production are parts of the strategy’s intention to build a collective ecological consciousness [
68]. In terms of green infrastructure there is no explicit reference to them, but the strategy is related to the respective Resilience Strategy that foresees the creation, conservation and enhancement of a quite wide range of green infrastructure assets, though without any provisions of connectivity amongst them [
71].
Paris En Commun involves citizens at various stages of the planning and implementation of the quarter-hour city. It is worth noting that 5% of the total budget of the strategy has been provided to enhance citizens’ participation in both decision-making and co-planning of their neighborhoods. Indicatively, since 2014, 2428 projects have been implemented from the “participatory budget” (Budget participatif de la ville de Paris), while the “municipal kiosk” has also a role in receiving and promoting residents’ proposals for funding through the participatory budget [
68].
Overall, the strategy of Paris en Commun uses the notion of “Hyper Proximity” to reconstruct the city as a patch of socially and culturally reach neighborhoods. Since the densely developed urban core provides for the most needed building density, the strategy focusses on improving the diversity of uses and creating an integrated mixed used urban fabric. Balancing the distribution of facilities amongst the 20 districts is a primary goal. By providing basic services at the local level, it is expected that all neighborhoods will have a variety of shops, homes, primary health and education services, offices and recreation opportunities, achieving the localization of important urban functions, strengthening each neighborhood as an entity. In general, locality and inclusion are evident in the proposed mix of land uses, with which residents group their activities around areas that once had only one use, while mixing of public and semi-public functions produce flexible public spaces and facilities.
Nevertheless, Paris has to counterbalance the risk of creating a socially polarized city. Paris en Commun is a plan concerning the inner ring area, only a part of the Greater Paris Metropolis, inhabited mainly by affluent Parisians and with property prices that rose even during the pandemic [
72]. Greening and pedestrianizing large parts of Paris may impose great challenges in providing inclusive and diverse housing and make the city of Paris inaccessible to lower-income suburban commuters [
72].
Table 4 summarizes the overall evaluation of the “Paris en Commun” plan based on the three pillars.