Tom Radulovich is the Executive Director of Livable City.
One of the pandemic’s most profound effects was on “third places,” those social spaces which are neither home nor work. Many such places—restaurants, bars, nightclubs and the like—either shut down or moved their operations outdoors. By necessity, San Francisco residents shifted much of our social life and some commerce onto streets and sidewalks. In doing so, we rediscovered the importance of public rights-of-way as social spaces of their own.
It’s always risky to declare the pandemic to be over. But in contemplating post-pandemic life, officials and businessfolk are keen to stabilize and revive the city’s hospitality industries, which employ more San Franciscans than tech and repopulate thousands of empty San Francisco storefronts.
Concurrent with Covid, a series of appalling attacks, particularly against Asian American seniors, has sparked widespread anxiety about crime on city streets. Fearing for our personal safety limits our freedom and compounds the social isolation caused by the pandemic, further eroding our mental and physical health.
Attention to how we light our streets and public spaces could help address several urgent challenges—from revitalizing commercial districts to helping nightlife and tourism recover to improving personal safety as well as simply making ourselves happier and healthier. A municipal street and sidewalk lighting strategy would figure out where light ought to go, where it ought not to go and its quality—in particular, the “temperature” of the light.
Some San Francisco street lights, like the Path of Gold light standards on Market Street, approach the problem artfully. Most of our street lighting is more quotidian—if not haphazard. Designed and installed in the mid-20th century, it dates from when streets were repurposed as conveyances for automobiles. The standards of the day favored widely spaced lights on high, arching poles, which wash light evenly over the roadway surface.
Sidewalk lighting was purely incidental. Effective pedestrian-scale lighting has been installed in a few places in the city, such as Jefferson Street in Fisherman’s Wharf, but it’s still an exception. The color of light was given little thought, and the lamps chosen were often the ones cheapest to install and maintain rather than those which provided the loveliest light. This has consequences for the light’s “temperature” a measure of its color, from red (lower temperature) to blue (higher temperature), not of the heat it gives off.
Over the course of a day, sunlight’s color temperature is lowest (reddest) at sunup and sundown, and highest, or bluest, at midday. Researchers are finding that moderate-temperature (warm white) light is optimal for reading and for recognizing objects. They’re also finding that exposure to high-color temperature lighting after sundown can disrupt our biological clocks—and our sleep—and disrupts the life cycles of other animals.
In the past, available energy-efficient lamps often had a very low color temperature (the orange glow of sodium-vapor lamps, like those on Market Street) or very high one (the harsh, bluish light of fluorescent tubes). The recent ascendancy of LED bulbs, which are energy-efficient and can be designed to provide light in any color temperature, gives us better choices.
The current highway-lighting ethos works best in cities without trees. Where the tree canopy is robust, little light reaches the sidewalk. San Francisco is still one of the country’s most treeless cities, but our tree cover has increased for the past few decades and expanding it is a civic goal. Street trees are a wise investment, with numerous benefits, from shade and moderating climate to reducing noise and air pollution, providing habitat for native birds and butterflies, and improving our happiness and mental health. As we green the city, we shouldn’t have to choose between healthy street trees and good sidewalk lighting.
Another problem with setting lights high is “light trespass.” Lighting the sidewalk is an amenity, but artificial light broadcast elsewhere—into residents’ windows, or the night sky—is pollution. There is strong evidence that light trespass is one of the causes of urbanites’ increasingly disturbed sleep, and it also disrupts animals’ habits, breeding and migration. Well-designed urban street lighting reduces light trespass by setting lights below the tree canopy, either on pedestrian-scaled poles or fixtures mounted on street-facing buildings, and shielding lamps to direct light downwards.
Lights on buildings—including wall lanterns, signs and awnings—can be part of an optimal street lighting system. Done well, pedestrian-scaled signs, awnings, exterior building lighting and lighting from storefronts improve urban safety and livability, and enhance the liveliness and character of neighborhoods. Done thoughtlessly, light from buildings, business signs and billboards becomes blight, degrading public spaces and making our neighborhoods less livable. Our Planning Code’s signage standards should be updated to ensure that commercial signs make better neighbors.
One hurdle to fixing all this is ownership. Over half of the city’s street lights are owned and operated by San Francisco’s Public Utilities Commission (SFPUC), with a few under the jurisdiction of other city departments. Most of the rest of our street lights are on poles owned by regulated utilities, principally PG&E.
In 2010, the city adopted its Better Streets Plan, which updated design standards and policies for sidewalks and streets. The street lighting standards were never completed. A few years later the city convened a street lighting task force, and in 2014 added a street lighting policy to the Better Streets Policy. Again, there was no implementation.
Residents and merchants understand the importance of lighting sidewalks well, but the city’s feckless approach to street lighting means they’re mostly on their own. The Valencia Corridor Merchants Association raised money to string lights down a mile of Valencia Street, including a Kickstarter campaign.
My Mission District block is typical in one sense, with the usual San Francisco tangle of overhead wires and only two streetlights clumsily fastened to utility poles. It’s atypical in that we have a lush canopy of trees planted several decades ago. During the day it feels like a green oasis, but at night it’s uncomfortably dark where the trees are most full. Years ago some neighbors strung lights under the trees to augment the block’s inadequate streetlights and make the street safer and more cheerful.
It’s great to empower and engage residents and merchants in designing and improving public spaces. But relying entirely on private initiative to provide something as fundamental to civic life as street lighting is a mistake. Good street lighting shouldn’t depend on how well-heeled or well-organized a particular block happens to be. Lighting the public spaces of the city efficiently and effectively is a basic function of city government.
Many cities are doing better than we are, and some are truly exceptional. The French city of Lyon is one lighting leader, having developed a lighting master plan decades ago. Lyon’s lighting standards aren’t one-size fits all; they include a menu of lighting standards for different parts of the city—from wilderness parks lit by the moon and stars to bright central-city commercial streets,—along with specific lighting plans for monuments like civic buildings, churches and bridges. Lyon approaches lighting as both an art and science and celebrates public lighting as public art in its annual Festival of Light,which draws Lyonnais and people from around the world every winter.
Let’s engage light to create delight. The lively marquees of neighborhood theaters or the neon signs and strung lanterns of Chinatown foster a unique sense of place. More monuments can be dramatically lit, as we have done with Coit Tower, the Palace of Fine Arts and The Bay Lights on the West Span of the Bay Bridge. We light City Hall in colors to celebrate holidays, sports teams and even solidarity with Ukraine. Getting sidewalk lighting right, and shining it only where it’s needed—and toning down billboards and other lighting clutter—will help our city to truly shine.