streetlights along straightaway A\J Photo © sergey02 \

I am lucky to live in the heart of the city, where I can walk or bike to work and play, and I’m only a hop and a skip away from a provincial park where I can lose myself in the woods and lakes for days. What I cannot escape is the ever-present glow.

When I look up at night, I can trace the outline of the big dipper with my fingers, and perhaps even Cassiopeia if it is particularly clear. To find any further constellations, I need to hold my smartphone’s star map to the sky to see what ought to be there.

I used to think of light pollution as inevitable. Growing up on the prairies, I could see towns from dozens of kilometres away, their orange halos staining the sky. We know the consequences of artificial light: harm to animals, interrupting human circadian rhythms and consuming 20 per cent of our electricity resources. Yet at no time in recent history, through our urbanizing and expanding, have we stopped to ask a fundamental question: how much light do we need?

Streetlamps and other night lighting have two obvious purposes: assisting navigation (primarily by car) and deterring crime. As society has urbanized, the expansion continued: lighting of office buildings at night to deter break-ins, personal security flood lamps on homes and, of course, the constant advertising of lit business signs. Does this illumination really protect us or just assuage our fears?

When it comes to preventing traffic accidents, we know that lighting is better than complete darkness, and we certainly need some to reduce risk, but how much is necessary? Very little research has been done. We do know that in rural areas, lighting plays a significant role in decreasing accident severity, depending on location. But in 2008, it was found that lighting on highways (not including intersections) decreases accident rates by less than 10 per cent. Thus, for longer sections, lighting could be determined based on the local circumstance, rather than following an indiscriminate standard. We know we need lighting at intersections, but on straightaways in urban environments (which already tend to have a lot of ambient light), we could likely reduce the frequency and brightness of streetlamps and not see an increase in accidents.

With regards to crime, the research is even more ambiguous. A study in the UK found that improved lighting did not decrease reported levels of crime or harassment. Increased lighting has been demonstrated to be effective on a footpath area in which locals already had a fear of criminal activity. Overall, though, it seems lighting has an impact on people’s fear of crime rather than crime itself. Some authors suggest that illumination may actually encourage crime. After all, criminals cannot operate very well in the dark. The emerging consensus is that while lighting should be targeted in areas of concern, the more important factor for decreasing crime rates is developing healthy communities.

Of course, there are other sources of light that have nothing to do with safety. Outdoor advertising, for example, is purely a wasteful consumption of energy. There is absolutely no need for a business to have lit signage after hours, and if they are only open during daytime, no need to have it at all.

Switch-off initiatives are spreading, particularly in the UK, where excessive lighting has been labelled a statutory nuisance. This way of thinking, though, has not yet been extended to North America in any meaningful way.

Do we really need as much light as we currently have? We don’t yet know for sure, but it seems like the answer is no. What we do need is better research and more data. Though light may prevent traffic accidents, ultimately it’s more important to ensure that drivers are skilled and sober (and encouraging public or alternative transportation is even more powerful). Furthermore, it is not light that deters crime – it is healthy communities. We know we have a problem with an overuse of artificial light. It is time to start looking for local solutions, and seeing where and when we can switch off. Where we can’t, we can look deeper: timing, direction and diffusion of every lamp should be considered at installation. It would be an arduous task, perhaps, but it would save money, improve health and protect the environment in the long run.

Myself, I will start by asking my condo board to turn off the glaring floodlight that bathes the parking lot (and my bedroom) for "security."

What will you switch off?

Learn more about why excessive lighting is detrimental to wildlife and how you can curb light pollution in the Night issue.

Alana Westwood is a Ph.D. candidate doing endangered species research in Nova Scotia. She was a member of the 2012 Canadian Youth Delegation to the UN climate change conference in Qatar, and you can follow her goings-on at

If you liked this article, please subscribe or donate today to support our work.

A\J moderates comments to maintain a respectful and thoughtful discussion.
Comments may be considered for publication in the magazine.
  • RT : Check out this issue of Alternative Journal where I'm a guest editor for 'InvestsInYou'. I hope this issue will ins… 17 hours 11 min ago
  • Environmental journalist Alexandra Scaman dives into a world of turbulent waters - investigating water equity issue… 5 days 10 hours ago