Bright idea? Light pollution fears shadow NCC plan to light up capital
Gabrièle Roy, Ottawa Citizen
Published on: July 28, 2017 | Last Updated: July 28, 2017 8:55 AM EDT
The National Capital Region is known for its distinguished Rideau Canal, breathtaking views and its historical landmarks.
Come sundown, though, the moonlight only illuminates a portion of Canada’s history.
A plan is afoot to brighten up some of Ottawa’s landmarks during the nighttime. Yet, many consequences will come to light as the city gets brighter.
After an analysis of the current evening condition of the capital region, the National Capital Commission developed what has been dubbed the Capital Illumination Plan in collaboration with the City of Ottawa, the City of Gatineau as well as private and public stakeholders.
Over a 10-year period, the NCC plans on showcasing the nighttime landscape of the capital region with the goal of “promoting sustainable development, enhancing the Capital’s nighttime beauty, enriching the resident and visitor experience and supporting existing planning, heritage conservation and urban design strategies.”
Since the NCC first presented the idea of a master lighting plan for the downtown core in 2014, the federal Crown corporation has called upon the public on a number of occasions. In 2016, a series of night walks were organized and participants were invited to provide their feedback for urban lighting plans in regards to the downtown core.
The draft of the Capital Illumination Plan was published in June and the final plan will be submitted to the NCC’s board of directors in the fall.
If approved, the plan will serve as a guideline for illuminating the capital at sundown.
A variety of Canadian landmarks have been selected by the NCC for illumination, including Confederation Boulevard, the 7.5-kilometre route connecting Parliament, the Supreme Court, Rideau Hall, the area’s museums and its embassies. Also selected have been the National Gallery of Canada, the Gatineau courthouse, Ottawa City Hall, Notre-Dame Cathedral and others.
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To illuminate the capital, the NCC suggests using “new lighting technologies featuring low energy use, greater control flexibility and a longer life cycle,” such as LEDs.
LEDs, or light-emitting diodes, have become a popular choice due to cost efficiency. However some of those involved with the Capital Illumination Plan, as well as scientists around the globe, have warned that artificial lighting, especially using white LEDs, can cause enormous repercussions for light pollution, as well as on animals, plants and humans.
The NCC suggests using light-emitting diodes from 2200K to 4200K. A 2200K LED will look yellowish to the eyes, while a 4200K will be a bright and bluish-white light.
“The 4000K light produces 16 times more light pollution than the 2000K,” says Dr. James D. Lowenthal, professor and chair of the astronomy department at Smith College in Northampton, Mass.
The more blue the light is, the more consequences there are for human health and on the ecosystem, notwithstanding the impact on light pollution and sky glow.
According to the International Dark Sky Association, “much outdoor lighting used at night is inefficient, overly bright, poorly targeted, improperly shielded and, in many cases, completely unnecessary,” which creates light pollution.
As cities get brighter at nighttime, the sky glow increases every year. “It’s been a six per cent increase every year for years, but it keeps increasing because of LEDs,” Lowenthal says.
Travis Longcore, assistant professor of architecture, special sciences and biological sciences at the University of Southern California. He offers a different critique: “Why would you light up a building that wasn’t built with lights on it? There’s something disrespectful about that. To me, this is just homogenization of the architecture.”
Yet, the NCC says it is aware of the consequences of light pollution and is promoting sustainable lighting. In its 120-page draft, the NCC provides information about lighting efficiency, such as the importance of equipment and orientation.
However, even if the luminaires chosen are well designed and facing downwards only, a lot of light can still go up into the sky, creating light pollution.
“The average city reflects about 30 per cent of its light facing down right back up into the sky,” says Lowenthal.
“Most people think asphalt is completely black, but it’s actually grey and it reflects plenty of light. In fact, it reflects much more light than the moon does,” says Lowenthal. (The moon reflects about 11 per cent of the sunlight.)
To reduce light pollution at night, the NCC’s senior land use planner, Sophie Acheson, says, “One of the most important features we have is the idea of these lighting curfews, where we suggest dimming lights at night, which was something that came out from our discussions with the public and some of the stakeholders.”
The draft suggests that lighting in certain areas of the capital be reduced by 50 per cent between midnight and 5 a.m.
Dimming the light will make a difference, says Lowenthal. “Whenever you dim the light, you’re making all the problems less bad. There will be less glare, less light pollution and, obviously, less energy waste.”
The NCC also suggests the use of motion-activated lighting in areas such as recreational pathways, parks, courtyards and parking lots. It also plans on avoiding light spills by using shielded luminaires whenever it is possible.
“Frankly I’ve been quite impressed with the NCC. Although there are a number of aspects I don’t necessarily agree with, they’ve done an admirable job at trying to find a middle ground,” says Robert Dick, the chair of The Royal Astronomical Society of Canada’s Light-Pollution Abatement Committee, who attended meetings for the illumination plan and provided feedback.
Dark Zones
Artificial light at night has severe consequences on wildlife and on the ecosystem. Plants have evolved for specific day and night cycles and respond to these cycles through the production and consumption of the hormone phytochrome, according to the non-profit International Dark-Sky Association.
If this cycle is disturbed, it can affect different species, as well as plants. In 2015, researchers at the University of Exeter in England published a study in which they found that artificial light at night affects the growth and flowering of plants, therefore also affecting the number of insects that use these plants for food.
The NCC recommends using lights carefully for areas where wildlife, plants, fish and insects cohabit.
To do so, the NCC says, it will create dark zones for major green spaces and waterways, such as Jacques Cartier Park and the Rideau Canal.
“One thing we are figuring out as we do this is that there’s a lot of knowledge out there now about how urban illumination impacts plants, so we are working hard to make sure we improve the impact of lighting in the Capital in those areas,” says Christopher Hoyt, senior architect with the NCC.
Longore says, “There’s a huge area of consideration that should be (given to) the type of wildlife in this area before going on with a designed plan, and I don’t see any of that yet. The NCC seems generally aware of the impacts of lights on wildlife, but not very specifically for the areas they want to put the lights in.”
Lighting will also be minimized for dark zones, allowing for events and showcasing things that might be located in those areas, but, generally, these zones will be kept as dark as possible.
There are some parks that should have no lights whatsoever, says Dick.
“If it’s done right, there’s enough sky glow from the city alone to find your way.”
Although the dark zones are a good approach to minimizing the effects of light pollution on wildlife and on the ecosystem, Dick worries the lights from other parts of the city might get bright enough to disturb the ecosystem, as is already the case for birds in the capital region.
Effects on birds
The sky glow of the capital region already has deadly consequences on birds in the area.
Anouk Hoedeman, founder of Safe Wings, says, “The issue with birds is that all of them migrate at night and they use the moon and the stars to navigate.”
“When there are bright lights, birds get disoriented and drawn towards the light, sort of like when you see insects all around a porch light.”
Safe Wings is a program of the Ottawa Field-Naturalists’ Club that’s meant to reduce bird deaths caused by window collisions.
As birds get drawn towards the lights, they collide onto buildings, fly around the light and collide with each other or even drop out of exhaustion.
According to a book published in 2006 called Ecological Consequences of Artificial Night Lighting, once birds are disoriented they are at risk of colliding with artificial structures such as buildings and transmission towers or of falling onto roadways and being run over by vehicles.
The night sky in Ottawa isn’t as bright as in big cities such as New York, Toronto or Chicago, but it’s bright enough for such collisions to happen.
“Most collisions are in the first two hours after sunlight, which tells us that the birds were descending into the city during the nighttime, when drawn by light pollution, and then collide in the morning when they want to be on their way again,” Hoedeman says.
Artificial lighting is one of a suite of human-wrought factors that together are contributing to the downward trend in distribution and abundance of the world’s numerous species of birds.
Every year, 250,000 birds die in Ottawa from collisions. Millions more around the world die from colliding with illuminated buildings.
Hoedeman says she’s glad the NCC’s plan articulates some of the dangers of light pollution, but says, “I would have liked to see a bit more about light pollution concerning birds and concerning humans.”
In the next couple of years, when walking the downtown core of the capital at nighttime, monuments, buildings, parks and public arts will be illuminated to create a more vibrant environment but there might be adverse effects.
“Even though the plan isn’t completed yet, we have already seen some of the impacts of it, the main being that people are now talking about lighting much more than they were in the past,” says Acheson.
Safety
The NCC says artificial light has a direct impact on the real and perceived safety of pedestrians, cyclists and drivers.
“When we are talking about public safety, we are recognizing the impact that lighting can have in crime prevention but also in terms of the universal accessibility,” says Sophie Acheson, the NCC’s senior land use planner.
The truth is scientists have been debating for years whether or not lighting increases safety in urban areas.
“There’s an assumption that isn’t tested that more light at night is better and safer,” says Dr. James D. Lowenthal, professor and chair of the astronomy department at Smith College in Northampton, Mass.
A 2015 research was done in England and Wales looking at whether reduced street lighting would affect road causalities and crime. Looking at geographically coded police data on road traffic collisions and crime in 62 local authorities, researchers came to the conclusion that there was no evidence that any street light-adaptation strategy was associated with change in collisions or crime at night.
“There are hundreds and hundreds of articles in the literature exploring the effects of light at night on safety, and I think it is safe to say that there are no consensus,” Lowenthal says.
What is light pollution?
Is the outdoor light on your front lawn shining upwards? If yes, you might be contributing to light pollution.
Light pollution is best described as the excessive and needless use of outdoor lights. For example, when a light is left on while everyone is asleep or when a light shines onto an area it shouldn’t, it causes light pollution.
The non-profit International Dark Sky Association uses four main components to determine if a light is causing light pollution:
- Glare – Excessive brightness that causes visual discomfort.
- Skyglow – Lighting that brightens up the sky.
- Light trespass – Light falling where it is not intended or needed.
- Clutter – Excessive and bright groupings of lights.
Either coming from buildings, streetlights or residential areas, lights that are needless cause light pollution.
The level of light pollution is often much higher is cities than in rural areas, because there are much more lights left on at night. It therefore makes it harder to star gaze in cities than in rural areas.
Colours matter
To determine the light pollution emitted from one light versus another, scientists subtract the two wavelength numbers and take that result to the fourth power.
For example, a 4000K light has two times the wavelengths of a 2000K light.
Therefore, taking the number two to the fourth power, scientists are able to demonstrate that “a 4000K light produces 16 times more light pollution than a 2000K light,” says Dr. James D. Lowenthal, professor and chair of the astronomy department at Smith College in Northampton, Mass.
“The colour of the light makes a big difference for light pollution”, says Lowenthal.
The blue-rich lights cause significantly more light pollution than high pressure sodium lights.
In 2016, the American Medical Association published a guideline on LED streetlights suggesting a limit of 3000K or less for outdoor lights.
The NCC is currently suggesting using LEDs as bright as 4200K.
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