Sotteville-les-Rouen is one of 58 municipalities in the Rouen metropolis to experience the extinction of public lighting at night. Since mid-July, part of the city has been plunged into darkness for a few hours, which generates energy savings and promotes biodiversity.
You may have walked around a city at night and found the street lights are turned off. We first think of a power failure as this dive into the dark night is unusual for us. In reality, it is most of the time a deliberate will, that of the municipality in question which can decide by municipal decree to switch off public lighting during all or part of the night.
In Sotteville-les-Rouen, this measure has been experimented with since the beginning of the summer, an approach already undertaken in 58 of the 71 municipalities of the Metropolis. Between 1 am and 5 am, a third of the town is therefore plunged into darkness. It is mainly the residential districts – that is to say a third of the population – which are concerned, the main axes of the city remaining enlightened.
In the middle of the night
But if some are delighted to walk in the moonlight, others associate the dark night with darkness! We must therefore reassure the inhabitants. “There are a lot of questions about insecurity and burglaries, explains Pierre-Arnaud Prieur municipal councilor of Sottevillais in charge of biodiversity and nature in the city, but when we present the figures and facts, especially that 80% of burglaries take place during the day, residents are less apprehensive“.
The function of urban lighting is to improve the safety of the inhabitants and to make the public space more user-friendly. The lamppost is a beacon in the night that some do not wish to deprive themselves of when they reign in their homes on foot. The municipalities are therefore trying to involve the population in their approach, by explaining the benefits of such a measure. This is currently the case in Barentin, where the population is called upon to express themselves this week on the extension of the experiment in the town.
The ecological and economic virtues of darkness
We know that turning off a light helps to save energy, we know less that night darkness contributes to the balance of biodiversity. Switching off the lighting at night therefore makes it possible to preserve the environment while respecting the flora and fauna, and to limit light pollution. Darkness would also calm road traffic, forcing motorists to slow down in poorly lit areas.
Why are we talking about light pollution? Because light when misused can have deleterious effects on animal and human life. Light pollution affects, for example, the migratory cycles of birds and disoriented them, or upsets our metabolisms by reducing our production of melatonin.
Or, light pollution can be easily reduced. Since 2018, the date of the application of a decree from the Ministry of Ecological Transition, store signs and advertisements have been extinguished between 1 a.m. and 7 a.m. everywhere in France. The decree does not concern public lighting or emergencies, but can already provide for saving 200 million euros per year.
According to theANPCEN, the National Association for the Protection of the Sky and the Night Environment, the quantity of lights emitted at night has continued to increase for decades: 94% in 20 years for public lighting. Or, one of the direct consequences of this nocturnal pollution is our difficulty in seeing the sky and its constellations. So if we are not owl like the cat or the owl that had night vision, we have the ability to roll our eyes and see the stars, which is a pretty good reason to turn off the lights and to fall asleep.