Let’s “Highline” the sidewalks of New York City
11 min read · Feb 1, 2024, (Bernardita Calinao, PhD)
The Highline is recognized as one of the world’s most acclaimed corridor parks. Visitors “can walk through gardens, view art, experience a performance, savor delicious food, or connect with friends and neighbors
— all while enjoying a unique perspective of New York City. “ (Friends of the Highline.org). Even the magazine Travel + Leisure ranks the Highline as one of the best places to visit in New York City.
This repurposed 1.45-mile elevated railway attracts approximately 8 million visitors a year. It has generated over $ 5 billion USD in new urban construction and 12,000 new jobs to the Chelsea neighborhood and Meatpacking District. It has contributed over $900 million USD in tax revenue to the city. Given the Highline’s astounding economic success, perhaps we should consider emulating its positive impacts, to a measured degree, on the sidewalks of New York City? Like the Highline, sidewalks in New York City are walking corridors. We can adopt the Highline’s park-like features, where possible. Implementation will be in keeping with how other world class cities create safe, beautiful, clean, and vibrant walking corridors. This means improving our sidewalks with minimal infrastructure change. Manhattan has over 900 miles of sidewalks and all five boroughs combined have an approximate total of 12,000 miles. It is the city’s largest public realm. Imagine if we could transform our city one sidewalk at a time?
Jack Robbins of FXCollaborative said that with the rise of shared autonomous vehicles (AV), fewer privately owned automobiles would roam our streets. This scenario could potentially free up approximately 17.2 square miles of on-street parking spaces, an area larger than Central Park which has 1.32 square miles. Imagine the extent of potential corridor space that the city can return to its citizens. This grand consequence of smart city transportation will expand our sidewalks. The sooner we know how best to use them, the more beautiful our city will be.
The idea of applying the Highline concept on sidewalks might seem preposterous. However, given the city’s challenges, such as declining foot traffic, desolation of office buildings, and the difficulty of converting commercial buildings for residential use, exploring this idea might be worthwhile. Moreover, a recent study (NAR 2023) reveals that 85% of Americans surveyed consider sidewalks as “somewhat important” to “very important.” Clearly, not all of NYC’s sidewalks are suitable for the idea, but many could benefit from it.
So how exactly do we “Highline” the sidewalks of New York City? Below are a few suggestions.
Keep walkzones free
There is one non-negotiable aspect we need to keep in mind before we “highline” any sidewalk — the walkzone. The walkzone is one of six sections of a typical NYC sidewalk, especially in those polycentric areas that attract visitors, commuters, and residents alike. The sidewalk sections include the building edge, frontage, walkzone, furnishing zone, curbzone, and crosswalk. The walkzone must always be free from obstructions, bumps, holes, cracks, and heaves. The unimpeded and safe flow of pedestrian traffic is most important and critical. The width of the walkzone should vary depending on calculated foot traffic. However, the rest of the sidewalk sections can be creatively “highlined,” where possible, to potentially craft that park-like corridor we all envision.
Adopt replicable Highline features
Many features of the Highline, such as trees, bushes, flowers, food, furniture, spaces for gathering and people-watching, artwork, architecture, and access points, already exist, to some extent, on our city sidewalks. Extending these features to a planned network of celebrated sidewalks will enhance the city’s open-street program, sidewalk shed reforms, and overall public realm improvements. We can emulate features of the Highline through a mindful and intentional commitment to enhance the appearance of our walking environment. “Highlining” the sidewalk is not about major construction; rather, it is about what we place on the surface like drought-resistant plants, flower boxes, native tree species, seating made from recyclable materials, shading — all of which will be vetted for safety, quality, design, and comfort. The Highline corridor exudes harmony, diversity, beauty, and interest. A rough and prudent estimate to add features in one Central Harlem sidewalk, for example, cost less than $50,000 US dollars.
Leverage on partnerships
While the sidewalks are owned by the City of New York, the responsibility for maintenance falls on the adjacent property owners. We can leverage on this relationship by offering incentives, possibly through funding, tax breaks, design guidelines, and collaboration. By embracing the sidewalk through public-private partnership, we can ensure the success of this initiative. Mykleby, et. al. in the book, The New Grand Strategy in the 21st Century, asserts that this country achieved its level of power and success, not through government work alone, but through a solid partnership with the private sector. The Highline Effect was realized through a strong collaboration between the Friends of the Highline and the New York City Government. Partnering with the real estate sector is another possibility given the commercial occupancy challenges they currently face. They can encourage their clients to stage not only the interior of their homes and buildings but also the sidewalk fronting their property. By 2030, 150 million home buyers and renters will be millennials (aka walking generation) and older adults (aka baby boomers.) They 4 seek walkable neighbourhoods. To them the quality of a property is no longer enough. They want a community that supports sustainability.
In many cities around the world, sidewalks serve as extended living rooms, as seen in Athens, Copenhagen, Lisbon, Prague, London, and even Seattle. These cities embrace their sidewalks by projecting the quality and character of the building edge. In New York City, dead zones are evident on the sidewalks of new property developments, including the Hudson Yards.
The city government, Business Improvement Districts (BIDS), adjacent property owners, community organizations, real estate, restaurants, and private companies can perform meaningful partnerships to enhance the character and quality of our sidewalks.
Align with climate change goals
Trees play a crucial role in lowering urban temperatures during the current climate crisis. A study conducted in 300 European cities shows that trees can cool urban land temperatures by as much as 53.6 degrees Fahrenheit in the summer. In the Netherlands, volunteers transported 1,000 native trees planted in wooden containers to several cities, including low-income neighborhoods. They called the project “The walking forest.”
Between 2007 and 2015, New York City planted one million trees as part of the PlaNYC program by then Mayor Michael Bloomberg, Dan Doctoroff, and organizations like Bette Midler’s New York Restoration Project. Despite this, however, NYC’s canopy cover remains at 22%, prompting a call across the five boroughs for the planting of another million trees.
Based on the 2015 tree survey, Walkspan, Inc. identified 40,579 sidewalks (equivalent to 1,544 linear miles) to be devoid of trees. This represents 24 percent of the 168,681 sidewalk block faces in the city. Following the example of the Netherlands, we can plant more trees to create a “walking forest.” This involves introducing native species planted in wooden containers, each with respective QR codes and soil sensors to alert the city’s Parks and Recreation team when the trees require watering. Trees in wooden boxes might just be the solution to address soil adequacy concerns in NYC.
Establish sidewalk imperatives
Here we explore sidewalk must-haves vs nice to have. Drawing inspiration from the ancient planners in Rome and Lisbon, who prioritized necessities such as beautiful drinking fountains every hundred steps and meandering stone mosaic sidewalks to celebrate and welcome residents and visitors, New York City can establish modest imperatives to enrich the walking experience. We can start with the following sidewalk imperatives:
Permeability. Permeability refers to the extent to which a building edge opens itself to the public. The vibrance of any city is evident at the edges and frontage of its buildings. Future building constructions must be required to incorporate permeable building edges to promote interest at street level — something to captivate passersby.
Sustainability. We must encourage everyone to walk as much as possible, and to limit driving to what is truly necessary, recognizing the climate crisis as a fossil fuel crisis. The Partnership for Active Travel and Health (PATH) has called on the governments at the COP28 climate conference to prioritize walking and cycling, with the aim of improving the quality of people’s lives and accelerating the realization of climate goals. According to PATH, enabling more people to walk and cycle can cut carbon emissions by up to 50%.
In the small English towns of Huddersfield and Todmorden, flowers on boxes and beds are replaced with vegetables. We can make NYC sidewalk gardens edible with vegetables resistant to heavy metals. Residents can give their time to promote planting vegetables anywhere possible. Flowers are beautiful but seeing residents help themselves with vegetables is better. Doing this will reduce food miles and save our planet.
Activity. Sidewalks must make room for music, dance, art, food, and clothing fairs. In Seoul, Korea, circular spaces next to walking corridors are designated for dance. Teens and hipsters gather, bringing their music, spending hours to practice and perform for passersby. These activities contribute to the revenue of nearby shops and restaurants. Central Harlem, for example, boasts the widest sidewalks in the city, surpassing even sections of the Highline. No need to create new spaces there.
Connectivity. The Highline has multiple access points to ensure easy entry into the park. Bike stations, subway hubs, and bus stops must function as welcoming gateways for soft mobility (aka walking).
Comfort. A city adorned with benches, chairs, and shading is a must. Copenhagen sets the example with public and semi-public seating throughout the city. In Austria, billboard columns serve a dual purpose — displaying cultural events and housing public restrooms. Comfort, along with safety, utility, and access, is one of the four important elements of walkability, as highlighted by Jeff Speck in his book, “The Walkable City.”
Safety. A safe walk is a walk that must be free from injury. Various initiatives are underway to ensure pedestrian safety, spearheaded by groups such as the NYC Department of Transportation and Transportation Alternatives. These projects are making excellent progress toward their Vision Zero goals.
Sense of Place. Sense of place arises from perception of space. To transform our sidewalks into corridor parks, we must steer away from visual monotony and uniformity. Each neighborhood must express strong ideas that give meaning to its unique experience of place.
Equity. Embedding equity means diversity and inclusion are reflected in all aspects of sidewalk improvement. Children, the elderly, people of all income levels and race must enjoy the social, economic, and environmental benefits of revitalized sidewalks.
Apply AI technologies
AI and the abundance of data have triggered a paradigm shift in the traditional urban planning process. The delivery of urban knowledge through detailed yet often fragmented spatial inventory and solutions, for example, has become faster and more accessible through data-driven technologies and AI. AI, in the form of location intelligence, democratizes the planning process. Today’s sidewalk simulation, scoring, mapping, reporting, and recommendation tools can shorten the length of time it takes to reshape the urban environment, allowing a process that is comprehensive, cost- effective, and time-efficient. Through data and location intelligence, we can operationalize Jane Jacobs vision of the American City and a smart city in its truest sense.
Reflect neighborhood aspirations
Getting the community involved is crucial when engaging in sidewalk placemaking. Neighborhood participation should begin at the onset. Residents need to feel a sense of ownership and should be given the opportunity to express their aspirations. Sidewalk upgrades must benefit those who live and work in the community. Every effort must be made to avoid gentrification by actively exploring how to help current residents. While transforming the sidewalks will undoubtedly change the area, the primary focus should be on ensuring that the benefits go to the people who already call it home.
Create a Department of Sidewalks
Creating a Department of Sidewalks in New York City was brilliantly proposed by Michael Pollock in his recent article, “We Need a Department of Sidewalks.” He provides details on the chaos and fragmented approach used in handling our sidewalks, presenting challenges in effectively managing the emerging complexities. Pollock argues that “Sidewalk chaos isn’t intentional. It happens because no one is empowered with the wide-angle lens necessary to cohesively see and address all of the sidewalk’s users and functions.” With the right lens, we might witness trash piles along sidewalks and other visual blights fade away. Pollock further asserts that having a Department of Sidewalks would be like appointing choreographers for Jacobs’ sidewalk ballet.
Contrary to his view that all responsibilities should solely rest on the city, I still believe that, in the spirit of placemaking, collaboration between adjacent properties and the city could contribute to creating a rich and diverse corridor landscape that reflects their aspirations.
I commend the NYC DOT for increasing the budget for sidewalks and implementing numerous improvements to the public realm, especially in realizing its Vision Zero goals. Safety remains a top priority. However, the dimensions of walkability extend beyond safety. The aesthetics of the sidewalk, its utility, comfort, interest, cleanliness, and vibrancy — add to the experience of walking. Jane Jacobs’ vision of a sidewalk ballet demands the choreography of diverse constructs.
“Highlining” will take to new heights the ambitious plan thoughtfully laid out in the New New York Action Plan. What better way to make New York work for everyone than by addressing conflicts where pedestrian density is at its highest? I can’t imagine a better urban strategy to make our city more inclusive than letting everyone enjoy our sidewalks. “Highlining” will increase foot traffic, address the challenges of desolation, office-to-residential conversion, project fragmentation and sidewalk jurisdiction. No major infrastructure investment is required. Instead, simply adding interesting, comfortable, and visually pleasing elements on the surface will enhance the quality of life while ensuring the safe and unimpeded flow of pedestrians.
What I’ve outlined is a bold vision for the sidewalks of New York City. It is ambitious yet incrementally achievable. If we do this, future generations will thank us. We certainly have enough neglected sidewalks to contend with; there is no need to search for and invest in another abandoned, above-ground railway.
Bernardita Calinao, PhD, is an environmental impact specialist and a long-time resident of New York City. She is the Founder and CEO at Walkspan, a New York City-based data and location intelligence start-up. Bernardita is also a Founder Fellow with the New York City Economic Development Corporation (NYC/EDC).