The river Thames “had an awful look”, Charles Dickens wrote in his Night Walks essay in 1859. “The buildings on the banks were muffled in black shrouds, and the reflected lights seemed to originate deep in the water, as if the spectres of suicides were holding them to show where they went down.”
By contrast, these days an illuminated London Eye ferris wheel rises tall above the river’s reflection of a well-lit South Bank. Big Ben upstream and downriver Tower Bridge are also beautifully lit. Even after dark, the riverside footpath connecting Westminster with the City is still lively and safe
This is no coincidence, according to Richard Mazuch, director of Design Research and Innovation at the IBI Group, who applauds such deliberate efforts by London’s urban planners to design for darkness — though he also insists more needs to be done.
“It is fascinating how, at night, buildings are denuded of their detail and colour,” he says. “Design that aims to create a holistic experience, whatever the time of day, is fundamentally different from oculo-centric design that focuses almost exclusively on appearance during daylight, in that it can have a tremendous impact on our lives.”
Across the Atlantic, understanding New York City’s culture was vital when the High Line, an abandoned elevated railway line that runs through Manhattan, was converted into a public park. The area was designed to be accessible by day or night, and its lighting system was build for impact. Low-energy LED lighting is installed below eye level to illuminate both the promenade and adjoining green spaces without creating overhead glare, so what you see are the lit areas rather than the light source.
“When you have light, you have shadows. Light creates contrasts. You need the light to create the dark,” says Hervé Descottes of L’Observatoire International, the High Line’s lighting designers. By avoiding blunt use of lighting, Descottes’ subtle calibration has made the High Line a favoured location for the Amateur Astronomers Association of New York, whose members gather weekly to observe the night sky without suffering from the light pollution that blankets the city.
Planning for the night
Learning to plan and design for darkness as well as for daylight is important for 24-hour cities like London. The night-time economy is said to be worth £66 billion a year and employs 1.3 million people in the UK alone. In the capital, new mayor Sadiq Khan has vowed to appoint a “night tzar” to champion London’s nocturnal industries.
Managing the balance between light and dark has many impacts on health and wellbeing. Moreover, urban design and planning that makes cities more pleasant at night offers a cost-effective and more appropriate alternative to costly clamp-downs on activities that are often deemed a cause of noise and nuisance, simply because they happen after dark.
“The introduction of artificial light is probably one of the most dramatic physical changes human beings have made to their environment,” says research scientist Christopher Kyba, chair of the International Dark-Sky Association’s night-sky brightness monitoring committee, who says that the current level of street lighting in many cities is too high, and cities often only feel dark by contrast.
The introduction of artificial light is probably one of the most dramatic physical changes human beings have made to their environment
There are also environmental considerations, Kyba says. The IDA estimates that in the US alone, 21 million tonnes of carbon dioxide per year are produced creating light that is wasted by unshielded lighting, equivalent to $3.3 billion (£2.3 billion).
“No one in the field wants to make streets ‘dark’,” he says. “What we want are effectively lit streets, where we will be able to see as well as or better than today, while at the same time greatly reducing both the total amount of light and the waste light.”
