Sensing Heat, Finding Cool: The Search for Water in Summertime Paris, New York, and London, 1880–1930

Abstract

At the turn of the twentieth century, Paris, New York, and London were epicenters of urban modernity, but these cities and their inhabitants were ill-equipped to cope with summer heat. Urbanites experienced thermal discomfort directly through their personal sensory registers, and the search for cooling water was a major, although overlooked, aspect of collective urban life in summer. Drawing on sensory and environmental history, and on the archives of city authorities and popular depictions of social life, we find that obtaining watery relief from the heat was limited by inequitable access to cooling infrastructures, including municipal and philanthropic baths and pools, which were often insufficient to meet urbanites’ needs. Instead, Parisians, New Yorkers, and Londoners turned to informal and often illicit methods to overcome the thermal inequalities that were baked into the brick and stone of their cities. Keeping cool in the melting metropolis was a challenge that demanded resourcefulness, bravery, and a willingness to disregard the rules and social norms that tried to regulate the use of other watery infrastructures, including ponds, fountains, hydrants, rivers, and canals. As present-day city authorities develop local adaptation plans in response to the global climate crisis, the fact that the coolness of water did not come easily or equally to turn-of-the-century urbanites should be at the forefront of our minds.

Paris, New York, and London have long been ill-equipped to cope with extreme summer weather. Residents suffered unequally when summer heated their bodies and homes in cities that were not built with high temperatures in mind. Neither Paris, New York, nor London featured summer-sensitive design in their architecture or layouts. The French newspaper Le Monde Illustré declared in summer 1884 that “Paris was not made for this season: there, it is possible to protect oneself from the cold, but it is impossible to escape the heat.”¹ In New York, “the intensest [sic] hot weather” came between June and September, peaking in August. Alas, “[n]o one studie[d] how it should be met, but all suffer[ed] immeasurably.”² This lack of attention to summer weather marked British cities, too. “London and London customs are ill-adapted to great heat” one newspaper reporter noted. The city’s inhabitants found themselves “languid and gasping.”³ Yet all thermal comfort was not lost; some individual and collective relief was possible. Water offered an essential way of finding coolness in the sweltering city.

The dramatic growth of Paris, New York, and London exacerbated summer discomfort. These three cities sweltered in summer even as they stood as epicenters of Western modernity.⁴ All had expanded rapidly in the nineteenth century, in ways that changed residents’ experiences of hot weather. Encroaching development turned accessible water bodies and waterfronts into industrial and commercial spaces rather than cooling respites. Landscapes once dominated by vegetation and tree canopy became sidewalks, streets, and blocks covered by brick, concrete, metal, and stone. Urbanization and changes in housing, technologies, food markets, and government policies have lessened some seasonal challenges in cities since the mid-nineteenth century.⁵ But urbanization also built heat into the modern metropolis.

Summer in the city has long been hotter than summer in the country. Even in the nineteenth century, the phenomenon now known as the urban heat island (UHI) effect intensified daily highs and extreme heat events in cities. The UHI is a universal characteristic of urban climates created by human activities and the modification of land surfaces.⁶ In the early 1800s, chemist and amateur meteorologist Luke Howard published the earliest report detailing how the orientation and form of London’s buildings and roads led to the absorption and storage of solar radiation.⁷ Howard identified four causes of urban heat storage. First, the geometry of a city can trap solar energy, preventing the radiation that withdraws solar heat from storage in the urban surface. Second, the grouping of structures can create a braking effect that blocks breezes and reduces the amount of heat carried away on the wind. Third, street drainage and sewers dry out cities, leaving less moisture for evaporative cooling. Fourth, anthropogenic sources of heat raise temperatures. Twentieth-century climatologists only identified one additional contributing factor: the thermal properties of urban materials. Urban surfaces have high thermal admittances, which means that they are particularly good at absorbing and holding heat. Landscapes dominated by stone and concrete absorb heat faster and store it in higher quantities than those dominated by plants, soil, and water.⁸ In 1899, one commentator noted how “a stench of hot asphalt and baked brick permeates London, and after hot, sleepless nights come hours of torment for man and beast.”⁹

The UHI magnified the feeling of summer. All three cities experience temperate climates with four seasons. For Paris and London, an oceanic climate generally brings frequent wet weather and mild summers, although Paris is slightly warmer, with summer averages in the high seventies Fahrenheit (mid-twenties Celsius). New York City sits at the boundary of the humid continental and humid subtropical climate zones, with hot, humid summers that average in the low eighties Fahrenheit (high twenties Celsius). All three cities have historically experienced summer highs above 90 °F/32 °C. Key climatic differences between the cities are, however, apparent—most notably New York’s humidity. A day with an air temperature of 90 °F/32.2 °C and 45 percent humidity feels like 93 °F/33.9 °C. But since humidity compounds the feel of heat, the same temperature with 70 percent humidity feels like 105 °F/ 40.5 °C. New Yorkers despised their city’s punishing humidity. As a humorous poem in the New York Age summarized in August 1890: “Why do I pant in want of breath/And long e’en for the chill of death/Feeling it must far better be/Than this vile thing—Humidity?”¹⁰ In a July 1911 heat wave, temperatures peaked at 100 °F/37.8 °C. But high humidity acted as “an agent of almost equal capacity with heat for causing discomfort to humanity”; “[t]he monstrous devil that had pressed New York under his burning thumb for five days could not go without one last curse.”¹¹ In London and Paris, high humidity combined with heat much less frequently, and was often associated with thunderstorms at the end of a heatwave rather than a summer-long sensation.

The very form and fabric of cities, combined with summer weather, subjected residents to episodes of extreme heat. We explore how, at the turn of the twentieth century, working-class and poor Parisians, New Yorkers, and Londoners sought relief from summer temperatures that the UHI effect exacerbated. A cold body could be warmed by a stove in the winter, but technology to cool a hot room or body remained elusive. Instead, for most city dwellers, respite from the “horrors of the stifling days” could primarily be found in water.¹² Across all three cities, baths, pools, shorelines, rivers, fountains, and—in New York, sidewalk fire hydrants—lured overheated urbanites seeking watery coolness.

Yet the modern metropolis could not meet the demand for summer coolness: it lacked sufficient infrastructure and adequate administrative responses. Urbanites were resourceful in their search for thermal comfort and often relied on informal measures that contravened municipal regulations. In Paris, New York, and London, innovative and sometimes joyful working-class geographies of watery coolness emerged when the mercury rose. The sensory dimensions of environmental experiences add a new thermal layer to the maps of cities. Heat’s typical impact on bodies and cityscapes established a collective sensory encounter with summer at the turn of the century. Visual culture and mass-produced newspapers captured (often with dramatic effect) experiences of heat and how residents sought coolness through water. This thermal layer of urban life furthermore reveals that summer weather was unevenly experienced in the modern city. The tactics urbanites used to cool off helped mark social distinctions between rich and poor, adults and children, women and men, and urban and rural life. Summer in the city has a unique sensory history.¹³

In Paris, London, and New York, many urbanites remained trapped within the sensory discomfort of the UHI in summer. One overheated Parisian demanded in 1884: “How can you find a little coolness to fight this fever that burns you, that you breathe in with the air?”¹⁴ Water was key to thermal comfort and health. As summertime heat crept into and transformed urbanites’ lives, city dwellers set out to make the most of the precious liquid on their journey to coolness. We begin by exploring the inadequate provision of bathing and other water-based cooling opportunities across our three cities and then show how urbanites sought individual and collective sensory relief through informal measures that flirted with illegality. This resourcefulness and flouting of municipal regulations led to bathing in prohibited spots and, in New York, hydrant cracking.

Unequal Sensory Histories of Urban Heat

Experiences of summer heat are politicized and situational. Class and power relations among different classes structured sensory experiences across Paris, New York, and London’s thermal landscapes. The histories we explore here expose the intertwined thermal and environmental challenges of summer that affected residents in strikingly unequal ways. In revealing these thermal histories, we contribute to an emerging critical heat studies agenda that seeks to move beyond a global, numerical framing of climate change and that challenges the normative emphasis on individual resilience. We take inspiration from the climate justice movement, recognizing that the impacts of a changing climate will not be felt equally. As Zoé Hamstead argues, “social-spatial segregation and built environment-related hazards co-constitute each other.”¹⁵ Temperatures and the means of thermal regulation are experienced unevenly across social groups and at granular scales (such as by neighborhood), at any given time, and across time. Furthermore, racial segregation and prejudices can limit access to cooling infrastructure, compounding the unequal distribution of thermal comfort created by class, gender, and the built environment.¹⁶ Questions of climate justice and injustice crystallize in the history of seasonal (dis)comfort in cities. As Hsuan Hsu argues, we are not just experiencing “a single, warming climate but a proliferation of vastly disparate micro-climates.”¹⁷ When intense summer temperatures became a shared urban experience, heat created new relationships to the city itself, remapping social geographies and provoking classed power struggles over access to water. City dwellers, individually and collectively, responded to the sensory inequalities of urban heat.

Ideas of health framed these responses to discomfort and heat exposure across the late nineteenth and early twentieth centuries. Summer was traditionally a season of ill-health and epidemics in cities globally, bringing epidemics of yellow fever, cholera, and typhus. The wealthy of Philadelphia and New York, for example, fled their cities during summer epidemics in the 1790s and 1830s, respectively.¹⁸ Since summer weather exacerbated decay, in the wrong environment (like a city), people believed that heat and humidity could potentially produce deadly miasmas.¹⁹ Yet even as germ theory gained ground in Europe and then the United States and fear of miasmas waned, older ideas about heat and disease remained. In New York, for example, worries about the dog days causing rabies persisted into the early twentieth century.²⁰

Class mattered too. When temperatures soared in the summer, wealthier residents had options. They could employ servants to operate punkahs and fans, laze in the shade, or purchase ice for cooling drinks and desserts. Unequal economic, cultural, and social structures shaped perhaps the most obvious responses to urban heat: escape. Well-to-do Parisians escaped to the breezy seaside resorts in Normandy and Brittany. Monied New Yorkers sought out the beaches of Long Island, Rhode Island, and New Jersey, or the woods of the Catskills or Poconos mountains.²¹ Wealthy Londoners decamped for fashionable resorts on the south and east coasts. With the wealthy in cooler climes, those who remained in the cities were exposed to sensory discomfort and real and imagined worries concerning heat and the seasonal cycle of disease.

Across all three cities, all classes of laborers who toiled out-of-doors—construction workers, icemen, deliverymen, and mailmen—suffered in hot weather. Fierce heat also impacted working-class employees indoors. New York physicians worried that workers in industries “where fires are required” were almost as liable to heatstroke “as though they were actively engaged in the midday sun.”²² The New York Tribune declared, “no class of people probably suffer more from the heat than those obliged to work in factories” like cigar factories, “where the windows are not allowed to be opened on account of the materials manufactured.”²³ New York’s sugar refineries were also terrible in summer; workers would collapse due to heat.²⁴ The laundry and tailoring trades were also punishing. In these clothing industries in London, “whether windows are open or closed, the air becomes vitiated during the heat of the long summer day. Perhaps the presser’s workshop suffers most heavily; windows are shut to keep in the damp atmosphere favorable to the work, and the heat rising from the steaming irons and wet cloth is intolerable.”²⁵

Workers’ homes were also hot. Chambres de bonnes filled the attic rooms of Parisian buildings built in the late nineteenth and early twentieth centuries. These attic spaces were originally envisioned as empty buffers for the sunlight and heat reaching the zinc or dark-colored roofs, to prevent lower apartments, where the bourgeois classes lived, from overheating. Yet attic rooms were often used as lodgings for servants. In a 1909 report on the living conditions of live-in employees, Paris municipal councilor Émile Massard described the chambres as spaces where “Air can rarely flow,” where “There [was] nothing to shield against the heat,” where “Maids […] are stifled under the roofs in the summer.”²⁶ Summer temperatures in small New York tenement rooms, where the working-class and poor lived and worked, could top 96 °F/35 °C.²⁷

Taking The Plunge

When homes and workplaces overheated, there were numerous ways to find sensory comfort through water. The need to cool down led to behaviors that digressed from ordinary conduct in an urban setting. Strolling across Paris in 97 °F/36 °C heat, one journalist described the “curious things” that he noticed: a man standing underneath a waterjet in the Palais-Royal gardens, an ice seller consuming his own merchandise, and a florist spraying herself with the water ordinarily used for the flowers.²⁸ For a concerned commentator in 1880s London, the oppressive summer heat meant that the “hot weather is serious … the flags are hard, the air is heavy.” Respite from the “horrors of the stifling days” could primarily be found in cool, pure water.²⁹ A journalist who broiled during a July heat spell in New York agreed. He averred that “the only relief” in the city “was in water, wherever it could be found.”³⁰ There was agreement that water was needed for comfort and health. Yet access to it was marked by inequality despite vast changes in the cities’ watery geographies.

By the 1880s, new water supplies and infrastructure—sewers, drinking water, and, in London and Paris, canals—had ushered in vast changes to urban health and social life. Social reform wrought environmental improvements in all three cities, including housing regulation, street cleaning, waste removal, parks, playgrounds, water fountains, and public baths. Water played a crucial role in nineteenth-century public health advancements grounded in germ theory, which provided a scientific rationale for upper-class cultural dictates around hygiene.³¹ Water also played an important role in the early-twentieth-century drive for physical fitness.³² The infrastructure of cleanliness and fitness, most notably baths and swimming pools, doubled as sanctioned spaces for thermal regulation. Modernization and urbanization created the urban heat island, but these processes seldom provided formal ways for urbanites to reduce the strain that city heat exerted on their bodies. Access to pools and baths was a key exception. The product of both private enterprise and municipal endeavor, such spaces were popular forms of infrastructure that urbanites reimagined as sites of summer cooling during periods of extreme heat.³³ However, repurposing the infrastructure of hygiene and fitness was far from straightforward.

Parisians could bathe in various kinds of public or private, permanent or seasonal, watery infrastructure. This included baths, swimming pools, and the floating summertime “bains de Seine.”³⁴ All offered Parisians “a refuge against the heat of the heatwave,” although they differed significantly in their price, cleanliness, location, and size.³⁵ Public establishments run by the municipal council were generally more affordable for working-class Parisians, while the cost and clientele of private facilities varied depending on their quality and location, ranging from affordable in working-class neighborhoods to expensive in high-end bourgeois areas.³⁶ In the 1890 s, Paris’s municipal council built three public swimming pools (Piscine Rouvet, Piscine Hébert, both in the nineteenth arrondissement, and Piscine Ledru-Rollin in the twelfth) for the health and well-being of urban dwellers.³⁷ The Piscine Rouvet was “located in a working-class area … surrounded by coal warehouses, refineries, foundries, mechanical installations of all sorts.” It welcomed “a clientele that [was] as large as it [was] interesting”, no doubt in part because it was free to enter. All three pools were popular among urbanites, and rising temperatures influenced the number of bathers; between 120,000 and 215,000 individuals visited each pool in July and August in the early 1900s.³⁸

Parisian pools of all types were popular places during the summer months. They could alleviate the sticky unpleasantness of heat on the body. One journalist rejoiced that “it is so pleasant, when everything around you is cooking, when the asphalt is boiling, when a fiery vapor is rising from the zinc roofs, when toasted leaves are falling from the roasted trees, to stroll under strips of cloth billowing in the breeze, to stroll in light underpants, sheltered from the relentless sun, within reach of a voluptuous, refreshing dip.”³⁹ The baths attracted “sweaty crowds” in search of relief.⁴⁰ Long queues awaited those who wanted to bathe “on very hot days … crowds of enthusiasts [were] lining up for an hour or more in front of the cold baths, waiting for the great reparative ablution.” And yet, once they reached this “paradise,” “all the cruelties of the wait [were] forgotten.”⁴¹ But these collective cooling spaces struggled to meet demand and proved ephemeral. Out of the eighteen cold baths registered in Paris in 1889, five remained open in 1921 alongside four public swimming pools.⁴² There were multiple reasons for the closure of the cold baths. They began to be seen as old-fashioned “remnants of another age” in comparison to the newly built permanent swimming pools from the beginning of the twentieth century.⁴³ And yet, cold baths remained popular among urbanites. During the heatwave of July 1921, bathing establishments had to turn away customers, as they did not have enough swimming trunks, towels, or changing rooms to meet the demand.⁴⁴

From the middle of the nineteenth century, the allure of the countryside enhanced the appeal of the rivers around Paris for leisure and cooling. By the end of the century, the naturally sandy riverbanks and amenities built for socializing were popular and drew Parisians outside of the city in their search for coolness. At the same time, affordable public transport and increased car ownership gave Parisians, especially wealthier ones, the option to seek coolness further afield.⁴⁵ Yet demand for cooling infrastructure in the summer continued to outstrip supply well into the twentieth century, and it was not until the 1950s that Parisians started to spend their summer outside of the city en masse.⁴⁶

Bustling spaces of watery coolness emerged in cities on both sides of the Atlantic. By the end of the nineteenth century, New York beaches lured thousands of residents on summer days and never more so than during a heat wave. City dwellers mobbed the outer-borough beaches on the south shore of Brooklyn and Queens, which offered relatively cleaner waters and large sandy beaches. Some New Yorkers rented bungalows or tents on these shores or along the Upper East River, in the East Bronx, and northern Queens.⁴⁷ The family of play-wright Arthur Miller had one such bungalow and recalled such crowds at Coney Island that it was hard to find a spot to lay a towel on the sand. Beaches could host half a million people during heat waves and holidays.⁴⁸ But as one local journalist took pains to note, although Coney Island was only six miles away from downtown Manhattan, there were “hundreds of thousands in town, bound to the bricks and the flagging like Prometheus to his rock, who find the city hot enough in all conscience.”⁴⁹ Work and other commitments, alongside a lack of resources, meant that not everyone could find relief at the beach.

Baths were a vital way of staying cool within New York’s urban core. While entrepreneurs had long run commercial floating baths, the City opened its first two seasonal municipal baths, open-air floating pools moored at Manhattan piers, in the summer of 1870.⁵⁰ These locations reflected the lack of private bathing facilities in tenements, home to what Harper’s magazine deemed the “class of our population who are most in need of thorough periodical ablution—by people who have neither the opportunity to bathe at home nor the means to pay for the use of private bathing institutions.”⁵¹ Readers knew “the class of population” who lived in tenements and used such baths. As the city’s worst, cheapest housing, tenements traditionally housed immigrants. In 1870, more than 940,000 people lived in New York; 44 percent of this population were foreign-born, and 99 percent were white.⁵² Increased immigration and the spread of tenements went hand in hand. By 1900, over 82,000 tenements housed 2.3 million New Yorkers. Five years earlier, the state legislature mandated that New York’s largest cities run year-round public baths, although years of delay slowed the law’s implementation.⁵³ Meanwhile, 97 percent of families living in tenement districts lacked bathrooms.⁵⁴ Defined by crowding, poverty, and ill health, tenements trapped millions of New Yorkers in substandard housing. From Harper’s to the writing of Jacob Riis, summer was synonymous with suffering in tenement districts.⁵⁵

Municipal authorities saw public baths as hygienic interventions. Many of the city’s reform initiatives grew out of elite paternalism, dismay with, and revulsion at the dire circumstances in which “the other half lived.”⁵⁶ The city issued time limits and restricted diving and relaxing on swimming platforms, but patrons nevertheless visited for cooling recreation.⁵⁷ While philanthropic baths had opened in the 1890s, New York City only opened its first year-round public bath in 1901. Located at the corner of Rivington and Goerck Streets, it served the overcrowded working-class and immigrant neighborhood of Manhattan’s Lower East Side. The tenements between the Bowery and the East River, which included Rivington, were known as an area of particularly intense suffering during “heated terms.”⁵⁸ Private charity and public indoor baths contained mostly shower stalls and lacked swimming pools. While more utilitarian than the floating baths, locals still turned to public baths to cool off.⁵⁹ Any opportunity to find relief was precious. “The heat of the tenements during the summer months,” one resident declared, was simply “oppressive.”⁶⁰

New York’s municipal and philanthropic bath operators counted visitors, sometimes noting gender and age demographics, but did not record racial demographics. Both types of baths were generally built in tenement districts that housed white, predominately immigrant, communities. At the turn of the century, as baths were opening, patterns of segregation and discrimination hardened, further segregating Black New Yorkers from the white ethnic enclaves most frequently targeted by reformers. It is reasonable to infer that most bathers in tenement district charitable baths and nearby floating baths were white.⁶¹ While the city’s Black population increased from 13,000 in 1870 to 60,000 by 1900, the city’s largest non-white communities, Black and Chinese residents, comprised only 1.8 percent and 0.02 percent, respectively, of the city’s 3.4 million inhabitants.⁶² The majority of the city’s population, including those who accessed cooling baths in summer, was white.

New York’s floating baths were unsurprisingly most popular in the summertime on very hot days. At the peak of the program in the early 1900s, the Department of Public Works oversaw a fleet of fifteen baths that hosted millions of visitors each summer (men and women used the baths separately). Each bath could fit 100 bathers at a time and hosted 4,500 bathers daily.⁶³ The years between 1901 and 1915 were also the heyday for public bath construction; the city built twenty-five new baths (sixteen on Manhattan Island alone).⁶⁴ Both types of baths offered sensory respite from the way humidity collided with New York’s UHI, and their popularity was seasonal: the public baths were significantly underutilized in fall, winter, and spring.⁶⁵ At the baths provided by the New York Association for Improving the Condition of the Poor, bathers set a record for the busiest day on July 22, 1899, and the record for busiest month in July 1900.⁶⁶ One municipal researcher attributed low patronage the rest of the year to the fact that association baths did not include swimming pools and demanded regimented behavior. Reformers had assumed a bathing habit would grow among tenement dwellers if baths were available. Interest, however, emerged seasonally, “through the three or four months of summer. But no such felt want exists to a general degree in cooler weather.”⁶⁷ Tenement dwellers valued water most for thermal relief and gymnastic fun, not necessarily for cleanliness alone.⁶⁸ After 1904, New York City began adding indoor pools to municipal baths, hoping to attract more users. It was not until the 1930s, however, when infamous Park Commissioner Robert Moses built the city’s celebrated outdoor swimming pools and modernized its beaches, that safe and playful summertime swimming became widely available. Moses’s pool network was also notable in that it catered to both Black and white populations, expanding swimming opportunities across the color line.⁶⁹ In the decades before his 1936 pool-building spree, however, New York had but five public pools, and just one outside Manhattan. Baths, not pools, cooled the urban core.⁷⁰

At both New York’s permanent and floating baths, visitor statistics reflected the increasing challenge of summer heat as the season wore on. In June 1911, 7,324 bathers visited the floating baths. July saw an increase to 654,299, and the number of visitors peaked at 812,952 in August. People often queued for access. The number of bathers fell to 334,625 in September and finally, at the swimming season’s end in mid-October, to 9,521.⁷¹ Clearly a seasonal necessity for thermal regulation, the city’s baths provided a vital—and oversubscribed—collective cooling infrastructure for many New Yorkers. During a hot spell in August 1906, a scuffle over access led to the arrest of Benjamin Silverman of Delancey Street; the court Magistrate who oversaw Silverman’s arraignment declined to hold him, saying he “appreciated how hard it was for one to hold his temper in hot weather.” Nonetheless, the judge fined him $5.00.⁷²

In London, meanwhile, inequality and shortages also marked access to water. Wealthier Londoners had long had access to plunge pools, spa waters, and floating baths, which provided opportunities for a cooling dip during periods of summer heat. For example, in the 1870 s, a privately owned and elaborately covered floating bath at Charing Cross apparently delivered filtered, aerated, and cool water and, at twice the cost of other first-class baths, offered an exclusive site for a refreshing dip.⁷³ Sensory comfort came at a price. Wider municipal provision was complicated by London’s parochial governance structures, but nonetheless from the 1840 s on, legislation allowed local authorities to build baths and wash houses for the working classes across the capital. Imagined by reformers and authorities as sites of cleanliness and decency, public baths also provided opportunities for escaping summer heat.⁷⁴ In 1888, the new pool at the People’s Palace in Mile End provided respite from hot weather in a neighborhood where a cooling swim was otherwise unavailable or unaffordable to the “decent poor.”⁷⁵ By the 1890 s, there were thirty-four public baths in London, including one on Caledonian Road in Islington (1892) and one on Mansford Street in Bethnal Green (1895).⁷⁶ By 1908, forty-four baths and pools had been built across the city.⁷⁷ These indoor facilities were supplemented by formally sanctioned and free access to bathing and swimming lakes in parks and open spaces across the capital. For one nineteenth century commentator, a long swim in Hyde Park’s Serpentine or Victoria Park’s ponds was “infinitely preferable to any cold or tepid swimming bath.”⁷⁸ By the early twentieth century, Londoners were able to take a cooling dip in eight bathing lakes, including those on Hampstead Heath.⁷⁹

In summer, these facilities were in high demand. Imagined as London’s seaside, the lakes in Victoria Park provided “temporary refuge from the heat.”⁸⁰ One observer enthusiastically estimated that the main lake received twenty to thirty thousand bathers over the course of a hot summer evening.⁸¹ Whether the estimate was accurate or not, contemporary photographs suggest that it was a very popular place to take to the waters to escape the summer temperatures.⁸² But as attitudes toward hygiene and exercise changed, so did access to such sites of thermal regulation. In the nineteenth century, the lakes in Victoria Park had been sanctioned as bathing ponds, providing an alternative to cooling off in the adjacent canal, but by the twentieth century, high demand and the associated poor water quality saw the ponds replaced by an open-air lido with a modern filtration plant.⁸³ The new facility’s large capacity of 1,000 bathers was nonetheless much less than the bathing ponds that it replaced. A tension existed between modernization and meeting the demand for thermal comfort. Reconstruction did make it easier for authorities to count the number of bathers. For example, the three baths owned by the Metropolitan Borough of St Pancras at King Street, Prince of Wales Road, and Whitfield Street attracted 248,069 bathers during the 1910 summer season.⁸⁴ A simple extrapolation of the St Pancras figures across all the indoor public baths in London at the time suggests that there could have been up to 3.5 million visits each summer (out of a city population of around 7 million). With such high demand, the facilities often reached maximum capacity, and prospective bathers had to queue for hours or were turned away altogether.⁸⁵

Inequitable And Unpleasant

Yet high visitor numbers hide patterns of inequitable access to the cooling properties of purpose-built amenities. Such spaces reflected and reinforced normative assumptions about the social and spatial segregation of public spaces along race, class, and gender lines. As Hsuan Hsu and Eric Dean Wilson have shown, in the United States, racial segregation historically denied Black people safe, dependable, and widespread access to cooling infrastructures, including pools and beaches, as part of what Hsu terms an “effort to reinforce the color line in thermal terms.”⁸⁶ While New York lacked state-sanctioned de jure racial segregation, de facto practices kept commercial leisure ventures and some public spaces racially segregated across the turn of the century. “No shore” existed, a city real estate expert said, where Black New Yorkers “would possibly be welcome” alongside white patrons.⁸⁷ As a New York Evening Post reporter observed, the lack of good recreation facilities was part of the problem of segregation in the city. White New Yorkers protested attempts to open bathing beaches to serve Black patrons; for example, Black real estate entrepreneur Solomon Riley tried to open the city’s first two such venues in the East Bronx in the 1920s. Both ultimately shuttered in the face of racially motivated lawsuits and investigations, and the Great Depression.⁸⁸

In London, municipal facilities were invariably segregated into first-, second-, and sometimes even third-class baths, reflecting and reinforcing the widespread division of leisure, transport, and other infrastructure along class lines in turn-of-the-century Britain.⁸⁹ In Paris, the offerings also catered to various classes, from cheap facilities affordable for laboring populations to high-end establishments for wealthy urbanites. The facilities differed in terms of price, cleanliness, customers, locations, and size.⁹⁰ On one end of the spectrum, the “elegant” pool in the wealthy Monceau area had sterilized water and a manager with “good morals” where young women could learn to swim and enjoy pâtisseries afterwards.⁹¹ On the other were the municipal pools constructed in the working-class districts and visited by the local laboring populations.⁹²

Cooling infrastructure similarly reflected and reinforced gender norms. Of the quarter of a million visits to the St Pancras baths in the summer of 1910, less than a quarter were by women.⁹³ Access to the fresh air and cooling water of outdoor ponds was similarly constrained; of London’s eight bathing lakes, five were open only to men, and in the other three, women were able to swim just one day each week.⁹⁴ Although Parisian women enjoyed more opportunities to bathe in the second half of the nineteenth century, most bathers were men.⁹⁵ The Piscine Rouvet was male-only, and the Piscines Hébert and Ledru-Rollin were only open to women one day each week. In the latter two facilities, the loan of a bathing towel and costume cost twenty cents for men and forty cents for women.⁹⁶ The combined effect of restricted and more costly access meant that the number of women visiting municipal swimming pools was low. During the particularly hot summer of 1911, out of the 102,887 people who visited the Piscine Ledru-Rollin, 99,815 were men, and 3,072 were women.⁹⁷ Paris’s private baths were slightly more accessible; some were only open to women, but had a considerably higher entrance fee of sixty cents. In New York, too, there was often very limited entry to such facilities for women, underscoring the highly gendered nature of access to the cooling properties of water in the summer.⁹⁸

For those who were able to access cooling infrastructures, visiting bathing establishments was a vivid sensory experience, one that could combine a complex mixture of welcome coolness and offensive revulsion. In 1896, for example, one Parisian observer described how “you venture shakily along a damp and slimy wooden boardwalk, striving to avoid the puddles of water that stagnate everywhere, rotting the poorly joined planks through which you can see gleaming, beneath your feet, the dirty, yellowish Seine.”⁹⁹ Eventually, “you dive into the yellowish water” of the bath. In doing so, bathers had to reconcile their disgust at entering the filthy water with the cooling properties of a swim. In 1897, another commentator went even further in describing what they had witnessed, writing that

even protected with the carapace of a diver, we would be repulsed to immerse ourselves in this impure sludge, and we wonder by what energetic fumigation those who come out of this pit of manure can be cleansed of the nauseating effluvia of a water that is greasy to the touch and which, if dried by rubbing both hands together, releases a very pungent odor.¹⁰⁰

One commentator used the oxymoron “fetid freshness” to describe the feeling of Seine water, encapsulating the complex experience of bathing in the river during this period. While the feeling of water on the skin may have helped Parisians cool off, they also had to contend with foreign objects (corps étrangers) present in the open waters of the Seine, including dead dogs, weeds, and refuse.¹⁰¹

In London, a disdainful observer similarly described bathing spots as “dingy, uninviting tanks, situated in dingy uninviting back streets,” full of “unsavoury liquids” that were invariably “something compounded of mud, water, and a stink.”¹⁰² One New Yorker reflected on his youthful summer days in the early 1900s spent swimming in the East River: “I often marvel that I did not contact typhus as I several times, at low tide when the water was muddy and filthiest, swallowed some of that water which contained the sewerage of several million people.”¹⁰³ In the 1890 s, a floating bath in Brooklyn, anchored near a sewer outlet, caused an eye infection outbreak. Even though New York physicians and sanitation experts repeatedly advised against swimming in harbor waters, and the city began filtering its floating bath-water due to pollution in 1914, public health concerns did not always stop people from taking a dip when a trip to the beach was impossible.¹⁰⁴ The inequities caused by class, gender, and poverty meant that thermal relief might only just outweigh the tactile, olfactory, and visual unpleasantness of urban waters.

Indoor and outdoor baths and, in New York, beaches, provided one way for city dwellers to adapt to summer temperatures and the UHI effect, often as an unintended consequence of attempts to cleanse the modern city and its people. However, access was constrained by official regulation, social norms, household economics, and inadequate provision. The potentially cooling benefits of water were also dependent upon individual judgments about the sensory compromises involved in using such infrastructure.

Informal and Illicit

To overcome the thermal inequalities that were baked into the urban environment, poorer city dwellers turned to temporary, informal, and illicit methods to secure the cooling sensation of water. Rivers and canals, fire hydrants, and fountains were reappropriated during the summer to provide fleeting sensory relief from the heat, revealing both the resourcefulness and creativity of city dwellers who were otherwise unable to cool down and the occasional benevolence of city authorities.

The Préfecture de Police de Paris—the authority charged with regulating the use of public spaces in the city—banned bathing in the open waters of the Seine, Marne, and canals in the middle of the nineteenth century.¹⁰⁵ According to the authorities, the ban was “in the interest of public decency” and to “prevent bathing in dangerous places.”¹⁰⁶ From the 1870 s, the Préfecture created designated areas of supervised bathing. Every year, bylaws listed the locations where river bathing was permitted. However, those areas were all located on the periphery of Paris, on the Seine, or its eastern tributary, the Marne.¹⁰⁷ The location and size of these official bathing areas were much criticized. Indeed, they were “too few or too far away for many laborers.”¹⁰⁸ One journalist declared: “Parisians, who believed you had the right to throw yourselves into the fresh waters of your rivers, think again! You have been granted 275 meters of Seine or Marne; that is really not enough.”¹⁰⁹

When baths and pools were unavailable because they were full, unaffordable, or too distant, the Seine offered an alternative, even if bathers risked being fined by policemen on the beat.¹¹⁰ In some rare cases, the agents in charge of public safety turned a blind eye, as was the case in the summer of 1899, when bathers were left to enjoy the open waters of the Villette and Bastille neighborhoods for nearly two weeks.¹¹¹ Despite the official ban on river bathing in Paris, some urbanites in search of freshness ventured into the Seine’s open waters in the city center to achieve a degree of thermal regulation. Open-water bathing in Paris was extensively documented by contemporaries, who took to their paintbrushes and later cameras to capture those experiences of respite from summertime heat in the coolness of water. Painter Georges Seurat famously depicted a scene of summertime bathing in the Seine in Asnières, a town on the outskirts of Paris (Figure 1). Une baignade à Asnières (1884) depicts a group of young, seemingly working-class bathers enjoying a quiet riverbank and cool water on a sunny day. And yet, respite from the heat and from the city appears limited. Buildings, chimneys, and smoke—standing in for the ills of modern urban and factory life—are an ominous presence. Although the bathers can access cooling water and leisure, the river in which they swim seems tainted by the pollution escaping from the activity in the background.¹¹² This contrast not only heightens the importance of water as a cooling mechanism, regardless of its quality, but also sheds light on the differentiated access to coolness and leisure that class distinctions fostered. The motif of riverine bathing, with visible class undertones, in or near the city persisted into the twentieth century. Although dangerous, the activity was often praised in the press, with journalists describing the “brave folk” who, unable to afford a trip to the seaside, turned the banks of the Seine into beaches (Figure 2). Scenes of urbanites’ enjoyment of the Seine’s waters during heatwaves were extensively photographed. Photos show groups of friends and families in the water, with the omnipresent urban activity and built environment in the background, and point to the key role that rivers continued to play in finding coolness in Paris (Figures 3 and 4).

Figure 1.

Georges Seurat, Une baignade à Asnières, 1884, oil on canvas, 201 × 300 cm, National Gallery, London. CC BY-NC-ND 4.0.

Figure 2. “Les baignades parisiennes,” Le Journal, July 3, 1914, 1.

Source: gallica.bnf.fr/Bibliothèque nationale de France.

Figure 3. Agence Rol, “7/7/23, chaleur à Paris,” 1923, glass negative, 13 × 18 cm.

Source: gallica. bnf.fr/Bibliothèque nationale de France.

Figure 4. Agence Mondial Photo-Presse, “A Ivry, vague de chaleur: bain libre,” 1932, glass negative, 13 × 18 cm.

Source: gallica.bnf.fr/Bibliothèque nationale de France.

Poor, young boys also braved tides and sewage pollution to swim illegally in New York Harbor. George Bellows immortalized East River swimmers in his 1907 painting Forty-Two Kids (Figure 5). Boys watched their peers clamber up pilings and leap from a dilapidated wooden wharf to splash among moored vessels, at risk of having their clothes stolen or being chased by the police for swimming in unsanctioned areas.¹¹³ Poet Walt Whitman celebrated New York’s youthful swimmers, extolling “The laughter, voices, calls, responses—the springing and diving of the bathers from the great string-piece of the decay’d pier … in to a transparent tea-color—the frequent splash of the playful boys, sousing—the glittering drops sparkling.”¹¹⁴ Whitman did not mention, however, the increasing problem of industrial and sewage pollution in New York Harbor, a problem for both Seurat’s Parisian swimmers and Bellows’ New Yorkers. And while youthful swimmers charmed the poet, they were often censured due to class bias. When Bellows used the slang “kids” in his painting title, he referenced gangs of young people associated with hooliganism and working-class immigrant neighborhoods. One art critic found Bellows’ subject “sordid”; another dehumanized the youth of this painting, claiming they resembled “maggots more than humans.”¹¹⁵ Middle- and upper-class New Yorkers considered such youth suspiciously, as a social problem, and even reform-minded citizens condemned them as “dock rats” akin to “homeless street boys [and] gutter-snipes.”¹¹⁶ Illicit swimming is a window into more than summer days; Forty-Two Kids is a window into how heat crystallized class biases and thermal inequalities in the city.

Figure 5.

George Bellows, Forty-two Kids (1907), oil on canvas, 42 × 60 1/4 inches, National Gallery of Art, Washington DC. This object’s media is free and in the public domain (more info from the gallery here).

Londoners had long sought relief from the summer heat in rivers and canals.¹¹⁷ Although smaller rivers, such as the Fleet, had been depicted by artists in the eighteenth century as popular places to cool off, by the late nineteenth century, most had been enclosed, subsumed into the sewerage network, and were unavailable for a cooling dip.¹¹⁸ Nonetheless, the city’s main river, the Thames, remained a site of thermal regulation (Figure 6). In his 1885 survey, Charles Dickens Jr. praised the river’s qualities as a place to escape the heat and cool the body: “Few things are pleasanter on a hot day than a plunge into one of the deep, quiet, shady pools in which the Thames abounds.”¹¹⁹ However, taking a cooling plunge from unauthorized places on the bank or without appropriate bathing attire could result in a fine from the Thames Conservancy, the organization charged with managing navigation on the river.¹²⁰ Taking a dip in London’s extensive canal network could lead to similar results. Although there are few written accounts of the cooling benefits of bathing in such watercourses, the frequency of newspaper reports covering arrests, fines, and fatalities associated with such behavior, particularly among working-class boys and young men, suggests that a swim was a regular occurrence during the summer heat.¹²¹ A 1905 photograph of boys bathing in the Grand Union Canal reveals some of the challenges facing urbanites when attempting to reach the glistening water. A tall retaining wall, several meters high, suggests a long drop from the street, while the lack of a towpath means there are few easy access points to get in or out of the water. In the foreground, several boys just manage to keep their heads above the water, presumably out of their depth in the middle of the canal.¹²² Canals were a watery infrastructure primarily intended for transport rather than cooling; contemporary reports described the efforts of canal company employees and the police to limit access to their water. However, the scale of the canal network and its porous boundaries meant that these efforts were invariably unsuccessful; when an illicit bather was escorted to the local police station, it left the coast clear for others to take the plunge.¹²³

Figure 6.

Boys swimming in the River Thames at Rotherhithe, London, 26 July 1934, © Daily Herald Archive courtesy of Science Museum Group. All rights reserved.

Rivers and canals were not the only places to seek coolness in the city. In New York, other types of water sources could temporarily transform a neighborhood. City leaders recognized that a city’s stone and brick held heat and sometimes ordered hydrants to be opened to lessen the UHI effect via evaporative cooling. In a heat wave, a mayor might order the Fire Department or Department of Street Cleaning to cool streets and bring down ambient temperatures, as Mayor Hylan did in 1923.¹²⁴ During that sweltering summer, La Prensa, a Spanish-language newspaper that catered to the city’s growing Puerto Rican population, noted “the hydrants in the streets were opened yesterday to refresh the environment a bit.”¹²⁵ During the city’s infamous ten-day heat wave in the summer of 1896, residents stepped into the spray of passing street-watering carts, and desperate mothers held overheated infants in hydrant waters released to cool streets.¹²⁶ Artist Power O’Malley captured a similar scene in his sardonically titled 1917 piece “The Bathing Season Opens.” It depicts not the wealthy on their inaugural shore trips of summer, but barefoot children, without swimsuits, playing in hydrant water (Figure 7). A uniformed official, one of the Department of Street Cleaning’s “white wings,” opens the hydrant. People bathing in water intended for street cleaning symbolized the discomfort of summer in the city. The UHI, combined with summer weather creates class-based bodily vulnerability to weather extremes that the government rarely addresses. What responses the city offered tended to be reactive, rather than systematic or proactive.

Figure 7.

Power O’Malley, The Bathing Season Opens (1917), Wallach Division Picture Collection, The New York Public Library. From NYPL: The copyright and related rights status of this item has been reviewed by The New York Public Library, but we were unable to make a conclusive determination as to the copyright status of the item. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. (Not in Artist Rights Society either)

During heat waves, the Fire Department might rig a sprinkler explicitly for cooling play.¹²⁷ Far more frequently, however, New Yorkers illegally opened hydrants to transform their local environment with water.¹²⁸ Youthful groups sometimes managed to wrench a hydrant open and jam a stick into the nozzle. Water spurted skyward, and the street became an outdoor shower.¹²⁹ In 1933, the New York Times claimed that 400 youngsters, identifiable by bathing suits and improvised skimpy attire, protested “against police interference with their heat-relief activities” outside the West 47th Street police station.¹³⁰ An open hydrant can release 1,000 gallons of water or more per minute; the pressure of the stream makes a hydrant difficult to close without the right tools. But the cooling effect of the water was worth the risk of arrest and the threat to domestic water supplies. The gushing fire hydrant has become a trope of the New York working-class summer.

Urban ornamental water features also provided iconic and illicit opportunities to keep cool. Located close to Fleet Street, the traditional center of London’s newspaper industry, the Trafalgar Square fountains and their basins became journalistic, photographic, and cinematic shorthand for summer in London (Figure 8).¹³¹ Just the sight of the “towering, splashing water was refreshing” for some Londoners.¹³² For those more intent on submersing themselves, the outcome of their endeavors was far from certain. The police were invariably quick to act when adults attempted to cool off in the fountain basins, even arresting some culprits.¹³³ In contrast, officers were often more tolerant of children’s paddling and bathing. For the “poor children to whom the seaside is denied” the water in the fountain basins provided an accessible place to cool off, despite reports of dirty and discolored water.¹³⁴ In August 1923, one newspaper reported that “scores of small children defied the perspiring policemen and paddled happily in the fountain basins of Trafalgar-square.”¹³⁵

Figure 8.

Still from Heat Wave—Trafalgar Square, London, c.1910, British Pathé Archive, 2338.28. All rights reserved.

Class and age played important roles in shaping who could access the cooling properties of water and where and when this was deemed appropriate by authorities in New York, too. In July 1925, as “the sun rose intolerantly over a baked and soaked city,” children jumped into the fountain in New York’s City Hall Park. Newspaper Row, the industry’s center on Park Row, faced the park, where an ornamental fountain tempted newsboys.¹³⁶ Looking on with a grin, Mayor John Hylan gave the police leave to let the children splash. Alternatingly fanning his face with his hat and mopping his sweaty forehead, Hylan remarked, “That cool water looks good to me. I wish I could join them myself!”¹³⁷ His response, while good-natured, spoke to the ad-hoc character of allowances made to mitigate summer in the city. Such municipal beneficence was not guaranteed—jumping into a fountain could result in legal woes for adults in New York, as in London. Earlier in the summer of 1925, in a June heat wave, theater district dancers jumped into the ornamental pool of the Maine Monument in the center of Columbus Circle. One woman received a court summons.¹³⁸

Swimming in urban waterways could bring more than censure to marginalized communities; it could be a dangerous and sometimes even lethal way to achieve thermal regulation. Non-swimmers or inexperienced ones drowned after striking submerged objects while diving or when overwhelmed, in New York Harbor, by strong currents.¹³⁹ London newspapers routinely reported an increase in drowning during periods of unusually high heat. In August 1876, The Times reported ninety-nine deaths from drowning during the preceding seven weeks, while the Daily Mail macabrely declared that the summer of 1899 was “the drowning season.”¹⁴⁰ The latter reported on boys and young men, primarily from working-class neighborhoods, who were carried away by powerful river currents, drowned in the wake of passing ships, or unable to haul themselves out of the deep water around docks and piers. Canals were hardly safer. In August 1913, for example, the Daily Telegraph reported on the case of six-year-old Isaac Monish, who drowned while saving a struggling friend who had taken a cooling dip in the Regent’s Canal.¹⁴¹ A year later, one reporter gloomily noted that “the canal takes a heavy toll in young lives.”¹⁴² The creative repurposing of existing infrastructure may have helped Londoners secure a degree of comfort in the face of torrid temperatures, but it was not without significant challenges and risks.

In Paris, too, bodies of water were sites of tragedy. In the early twentieth century, drownings made up a third of accidental deaths in France and occurred almost solely in the summer.¹⁴³ Between 1895 and 1913, the Paris morgue received an average of 295 people each year who died by drowning.¹⁴⁴ The police recorded some of these incidents. In July 1908, they opened an inquiry into the death of Eugéne Lepelletier, who drowned in Sylvain Arnould’s river bath in Joinville-le-Pont. The next year, in August 1909, Camille Léonard “had wanted to bathe immediately after eating and sank [like a stone].” In August 1910, Paul Delpech, described as “timorous” because he was not able to swim, was led into the water of the river bath “Banc de Sable” by his cousin. There, he lost his footing and tried holding onto another bather’s leg who, thinking he was the target of a prank, shook him away. Upon seeing this, the lifeguard jumped in the water to intervene, but Delpech drifted away in the confusion. His body was only found forty-five minutes after the incident took place.¹⁴⁵ Concern for the safety of individuals had been one of the original drivers for the Préfecture de Police to ban bathing in the Seine. Despite ordinances banning harbor swimming in New York, summertime drownings remained a concern into the 1930s. Near the decade’s end, Park Commissioner Robert Moses launched a free swim lesson program for both young people and adults to address the city’s 400 annual drownings.¹⁴⁶ As more people were taught to swim in the twentieth century, fewer people drowned as they tried to keep cool.

Conclusion

In Paris, New York, and London, heat was an unseen element of the urban environment, but it was felt intensely within the body—the feeling of hot air in the lungs as well as on the skin. The high humidity of New York intensified the thermal discomfort of the UHI. Due to its porous nature and highly sensory faculty, the skin was central to both attempts to cool off and the experience of bathing. Descriptions of the skin encountering water were often made in vivid sensory terms, invariably reflecting a compromise between the feelings of pleasure and disgust that the water and its associated facilities could arouse. Keeping cool in the modern melting metropolis through the refreshing properties of water was an individual and collective challenge. It necessitated resourcefulness, bravery, and a willingness to break rules (whether cracking a hydrant or swimming in prohibited places).

An innovative, and sometimes joyful, working-class geography of watery coolness emerged each summer as the mercury rose. There were similar water activities occurring across London, New York, and Paris. Most notably, all three cities lacked sufficient and inclusive access to swimming pools, public baths, and sanctioned bathing places to cool all residents. Heat and climatic conditions, more generally, were experienced on multiple scales. Water-cooled individual bodies with individual preferences. But the search for and experience of coolness was also often communal, as people swam together in pools and rivers and shared the water that gushed from hydrants. The unintended and informal uses of fire hydrants, ornamental fountains, and commercial waterways to cool off illustrate how urbanites adapted infrastructure to their own purposes. In aggregate, these decisions reveal a social history of cooling off.

Our focus on the experiential and the everyday complements and builds on research into more recent extreme heatwaves, and shows how the search for cool has long been an everyday sensory practice in the modern urban heat island.¹⁴⁷ Heat is socially produced in specific built environments and eras. By the late nineteenth century, urbanites knew that summer, combined with what we today call the UHI effect, fostered new, city-specific sensory effects. As Harper’s magazine observed, big cities, like Paris, London, and New York, were “pretty bad places in midsummer. The bigger they are, and therefore the better as cities, the more intolerable they become in July and August to folks who cannot leave them.”¹⁴⁸ Yet city leaders and reformers seldom responded adequately or inclusively to the challenge of summer heat. Access to the cooling properties of water was shaped by inadequate municipal provision, inequitable gender norms, economic inequality, individual sensory perception, and attitudes toward risk. Coolness did not come easily or equally, and not everyone was able to secure it. Urbanites were forced to be resourceful, adapting to daily summer highs and punishing extreme heat episodes with behaviors that bridged both the legal and illicit. In all three cities, collective responses established urban vernaculars for keeping cool.

The effort needed to keep cool has persisted. Even as cooling strategies shifted from water to air conditioning in the twentieth century, there remained a sense that hot weather was to be largely endured by individuals. The use of air conditioning increased in commercial buildings in New York in the 1920s and in London and Paris beginning in the 1930s. Climate-controlled theatres, department stores, and hotels beckoned the overheated, reconfiguring thermal experiences of summer. But the air conditioning revolution was far from complete, and the core ways to cool down remained very similar to those of the late nineteenth and early twentieth centuries. Urbanites continue to seek out water to stay cool. Parisians today bathe in the now officially clean Seine, with the 2024 Summer Olympic Games injecting money and publicity into river swimming.¹⁴⁹ The New York City Department of Parks and Recreation, meanwhile, publishes a map showing where New Yorkers can cool off in water at beaches, pools, and playgrounds where sprinklers keep children refreshed and content.¹⁵⁰ Twenty-first century Londoners can enjoy lidos, whose financial stability is far from guaranteed, while developers dream of a return to floating baths on the Thames.¹⁵¹ Urbanites today face shared environmental challenges in summer due to seasonal hot weather, the urban heat island effect, and hotter, more frequent, and longer heat waves caused by climate change. To the extent that there will be solutions to summertime extreme heat, they will not be purely technological but local and collective, based on a city’s weather, political will, community needs—and inclusive access to the cooling properties of water.