How to Cross the Road without Getting Your Feet Wet
The design of the urban street is simple; a certain number of lanes in each direction framed out by raised sidewalks on one, or both sides. The cars and the people are separated by a 15-centimeter separation that acts as a visual and physical barrier. Cities all across Canada and much of the developed world follow this simple design premise. But where does the curb come from and is it really the greatest, safest and most efficient design for the urban street?
Evidence of sidewalks has been found in archeological explorations of ancient civilizations, however, the modern design of the grade (ground level) separated footpath only dates back to the late 18th century. At this time, waste and byproducts of the industrial revolution were filling the roads at an exponential rate and the lack of separation between the people and the street was causing bacteria and disease to spread. Raising the sidewalk ensured that waste was kept in the street, even when it rained. Later, as cars became more widely used, the raised walkways also served as a safety feature, preventing cars from swerving into the path of pedestrians.
Fast-forward about a hundred and fifty years and raised sidewalks are the norm in virtually every city in North America. And while a few problems were being solved, it was quickly becoming apparent that the 15-centimeter step between the sidewalk and the road was a huge barrier to many, including the disabled population.
The idea for the curb ramp (also known as curb cut, a cut-out slope that bridges the gap between the sidewalk and the road at an intersection) reportedly came out of Kalamazoo, Michigan where a disabled lawyer who primarily acted for disabled veterans petitioned the City Council who agreed to build test ramps at a couple of intersections . However, the 1970s curb cut movement in Berkeley, California is much more widely celebrated as the birth of the curb cut. In this movement students rallied to have an accessible route through the University of California campus and the town of Berkeley . Regardless of where they first appeared, curb cuts were soon adopted in virtually all cities that already featured raised sidewalks.
In Toronto, the Accessibility Design Guidelines released in 2004 states “curb ramps should be provided wherever there is a difference between the sidewalk, or a pedestrian pathway, and the road surface at all street corners, or wherever pedestrian crosswalks are provided.” Additional guidelines provide specifications for length, width and allowable slope as well as promoting the use of colours or material finishes to allow visually impaired users to easily identify these areas 
We have elevated sidewalks that keep us away from any debris that might be in the road, keep us safe from cars and we have ramps from the curb to the road to allow those in wheelchairs, pushing a stroller or using a walker to cross the street with ease and all of this is documented in codes that engineers and contractors must follow. So, is there a problem? Despite being a design that looks to be fine on paper, at this time of year when snow melts and rain falls, I can’t help but wonder whether curbs and curb cuts are leaving us pedestrians in a puddle.
It’s quite evident that Canada and Toronto specifically has a vastly different climate than Berkeley California. In light of that, perhaps it is time to reconsider the curb cut, which at times seems to create a perfect catch basin for rain and slush and making the intersection practically ‘uncrossable’ for everyone, not least of which, the disabled population they were originally designed for.
Several communities around the world have designed and constructed streets that look different than the typical ones we see in Toronto.
CASE STUDY: Curbless Streets, Exhibition Road, London, UK
The revitalization of Exhibition Road in London provides a good example of a “no-curb” approach. The idea to put cars and pedestrians back on the same level came from a Dutch traffic engineering . He argued that in urban environments, removing signage and signals would actually improve safety and increase mobility for both cars and pedestrians and soon cities around the world began to consider it as a possible solution to some of their transportation issues .
Exhibition Road is a popular tourist area in London and had long been experiencing issues with congestion. In December 2011, a massive renovation project was completed which simplified the street by removing all signage and curbs . At the same time, a 20mph (32km/h) speed limit was implemented, visual and textured lines were painted on the pavement and lighting quality was improved . No barriers were used but drainage channels on the roadway help to distinguish pedestrian areas while also helping to keep the road clear from water accumulation . So far, this transformation has been praised for keeping people safe, being accessible and improving traffic flow. Despite the reduced speed limit, having the entire street on one level allows for flexibility in number of lanes over the span of the road and has actually allowed vehicles to travel more quickly compared with the previous design .
CASE STUDY: Raised Intersections, Various cities, USA
Raised intersections are another idea that has the potential to make crossing the street both safer and more accessible. Raised intersections essentially bring the road pavement up to the sidewalk rather than bringing the sidewalk down to the road as is done through use of curb cuts. As a result, pedestrians are able to cross on a level surface and cars are slowed by the hump in the road, which resembles an elongated speed bump . Another benefit is that water will naturally flow away from the intersection.
Raised intersections have been implemented in a number of different cities in the US including Phoenix, South Beach and Charlotte . In general these applications have been focused on using the raised intersection as a way to calm traffic rather than as a way to help with storm water drainage. There has not been any data yet on whether these intersections improve pedestrian safety however, one potential issue with them is that depending on the slope of the intersection, emergency vehicles may be forced to slow their speed down by up to 15mph (24km/h) .
CASE STUDY: Permeable Intersections, Michigan, USA
Permeable concrete is concrete that has more holes than regular concrete, which allows water to flow straight through. Its development has been largely tied to sustainability efforts as it allows water to drain back into the ground rather than be directed into our sewers when it rains.
The City of Ionia in Michigan used permeable concrete to repave an entire intersection in 2012 . The intention was to test this as a method for dealing with storm water issues caused by the steeply sloped streets and river adjacent to the city . While being praised for its effectiveness in water drainage, permeable concrete tends to be much more expensive than traditional concrete and requires different maintenance practices, especially in the winter . However, one idea to reduce costs would be to use a hybrid approach and pave the intersection in traditional asphalt cement and have strips of permeable concrete at the crossings or just at the base of the curb cut.
These are just some ideas for how to redesign a part of our urban landscape that might at first seem impossible to change. As our population ages, accessibility is a growing concern in many Canadian municipalities, including Toronto., Streets and intersections play a huge role in the ability for people with mobility challenges to live independently. As has so often been found, designing for accessibility is designing for everyone. We all have something to gain whether it’s being able to easily maneuver the streets in a wheelchair or simply cross the road without getting your socks wet.
Hilary Whiting has a fascination with urban environments which is informed by her background in civil engineering. She loves seeing how people, infrastructure and nature collide in our cities. Her main area of interest is transportation where she is looking at how infrastructure can be better engineered to improve urban safety, accessibility and sustainability.
 “The Curb Ramps of Kalamazoo: Discovering Our Unrecorded History” Steven E. Brown, 1999. Retrieved on March 29, 2016 from http://www.independentliving.org/docs3/brown99a.html
 “The People’s Sidewalk” Bess Williamson, 2012. Retrieved on March 29, 2016 from http://www.boomcalifornia.com/2012/06/the-peoples-sidewalks/
 “City of Toronto Accessibility Design Guidelines” The City of Toronto, 2004. Retrieved on March 29, 2016 from https://www1.toronto.ca/static_files/equity_diversity_and_human_rights_office/pdf/accessibility_design_guidelines.pdf
 “Curbless Streets in Urban Contexts” City of Austin, 2007. Retrieved on March 31, 2016 from ftp://ftp.ci.austin.tx.us/PWD_ESD/EngineeringServices/Second_Street/Archive/ADA_Coordination/05%20Curbless%20Streets%20Research%202007-07-30%20pub1.pdf
 “Exhibition Road” The Royal Borough of Kensington and Chelsea. Retrieved on March 31, 2016 from https://www.rbkc.gov.uk/subsites/exhibitionroad.aspx
 “Raised Intersections” National Association of City Transportation Officials. Retrieved on March 29, 2016 from http://nacto.org/publication/urban-street-design-guide/intersections/minor-intersections/raised-intersections/
 “Traffic Calming Measures – Raised Intersections” Institute of Traffic Engineers. Retrieved on March 31, 2016 from http://www.ite.org/traffic/raised.asp
 “Pervious Concrete Intersections, City of Ionia” Prein & Newhof. Retrieved on March 29,2016 from http://www.preinnewhof.com/projects/pervious-concrete-intersections/