Here are some answers to some frequently asked questions related
to traffic issues.
Traffic Control Signals
a traffic signal know if a vehicle and/or a pedestrian is present?
are two types of signal operations: Fixed Time signals and Semi-Actuated
signals are normally installed at the intersection
of two major roads (ie Yonge Street and Dundas Street). Fixed time
signals constantly cycle in sequential order and do not depend
on any type of detections such as pedestrian push-buttons. All
roads and movements are served in a constant specific order.
signals are typically installed at the intersection
of a major road and minor road (ie. McCowan Road and Brimorton
Drive). In these cases, the signals remain green on the major road
(McCowan Road) until a vehicle or pedestrian is detected on the
minor road (Brimorton Drive). Vehicles on the minor road are detected
by electromagnetic wires (loops), which are imbedded in the pavement
on the side street near the stop bar.
Pedestrians are detected by the pedestrian pushbuttons. This tells
the traffic signal to change to green for the minor road and gives
pedestrians sufficient time to cross the main road (McCowan Road)
and/or receive a pedestrian signal display.
Here are some common misconceptions motorists have at semi-actuated
traffic control signals:
If I back up and drive forward again, the signal change quicker
- This does not work. The detector mechanism does not count the
number of vehicles waiting.
If I get out
of my car and push the pedestrian button, the green light comes
on quicker – If
the traffic control signals are functioning properly, the pedestrian
push-button does not make
the green indication appear sooner. However, it can make the green
light longer at some semi-actuated signals since it takes longer
for a person to walk across a street than it takes for a car to
drive across a street.
really necessary for me to push a button to activate the pedestrian
I just wait for the light to change?
push buttons are not provided at busy intersections ((ie Yonge Street
and Dundas Street) since signal displays change
from street to street all day long. However, at a major road/minor
road intersection (ie. McCowan Road and Brimorton Drive), the side
street will not change to green until a vehicle is detected or
a pedestrian presses the button.
do some signals, which have pedestrian displays, show a “Don’t
Walk” indication even when the
signal is green for the side-street (minor road)?
occurs when a vehicle has been detected on the side-street and
has pushed the button. This only
can occur at locations where the City’s Transportation Staff
has installed a Semi-Actuated “Type 2” (SA2) intersection.
With this type of operation, a pedestrian must push one of the
pedestrian push buttons to receive a "Walk" signal. When
a button is pushed, a pedestrian will receive a "Walk" signal
with sufficient time to cross the major road. If a button is not
pressed and the traffic control signals respond to a vehicle only,
a green signal will be displayed along with a "Don't Walk" indication
for pedestrians. The length of this green signal could be considerably
shorter than the required walk time for a pedestrian because the
length of the green signal is variable, based on the vehicle demand
only (as the pedestrian push button was not pressed).
We use this type of operation to maximize the efficiency of the
intersection. It serves to minimize delay for the relatively heavier
volume of traffic on the major road.
It is the City’s
practice to always install pedestrian information signs, which
describe this operation at these types of intersections.
I get half
way across the street and the “ Flashing
Don’t Walk” indication appears. Do I still have enough
time to complete my crossing?
pedestrians misunderstand the “Flashing Don’t
Walk” or "Helping Hand" display feature. This feature
is intended to warn pedestrians who have not started to cross that
there is not enough walk time left to start and complete their
crossing safely. If they have started to cross and the "Helping
Hand" indication appears, there is still sufficient time to
complete their crossing. The duration of the "Helping Hand" indication
is included in the calculation of the pedestrian walk time. Where
this feature is installed, it is augmented with information signs
to explain the operation.
Pedestrian walk times are calculated based on the walking speed
of a typical adult (1.2 metres per second). At locations with high
percentages of senior citizens or children, walk speeds are reduced
to 1.00 metres per second to accommodate a slower walking speed.
It is difficult
for me to turn left because there is no left-turn feature and
there are no gaps in the heavy traffic coming the other
way. Can I turn left on the amber and/or all red if my vehicle
is within the intersection?
volumes are low and motorists are not experiencing significant
cycle delays, it is expected that motorists will turn
on the amber. During the all red phase, all signal heads are showing
red and all traffic is stopped. Vehicles are not allowed to proceed
through the intersection until the all red signal is over. This
gives left-turning motorists the opportunity to legally clear the
intersection in safety before the other directions begin to move.
Generally, the all red phase is two to three seconds in duration
dependent on the width of the intersection.
does the Left-turn Green Arrow or Flashing Advanced Green sometimes
and other times not?
advance features can be programmed to operate during specific
periods of the day. Where warranted, these features
are typically programmed to operate during the morning and afternoon
peak periods, when left turn demand is highest.
vehicles are detected by “detector loops,” which
are embedded in the pavement at either the stopbar or at a distance
of approximately three car lengths back from the stopbar in the
left-turn lane. At locations where the latter is in place, only
the third vehicle in a left-turn queue will activate the left-turn
priority feature. This type of operation serves to maximize the
efficiency of the intersection. We assume that two vehicles will
normally safely clear the intersection during the amber display.
to wait a long time to turn left because the existing left turn
green arrow is
too short. Why can’t the city allocate more green time
to the left turn green arrow so that left turn delays can be
development of signal timing is a “balancing act” where
the City tries to allocate movement fairly to all directions. In
some cases, the City would prefer a longer left-turn priority feature
but often is constrained by high traffic volumes arriving at the
intersection from other directions. For instance, if we add more
time onto a left-turn priority feature we must remove “green” time
from other traffic movements.
do I sometimes get stopped at every every signal, while at other
times I can
travel through consecutive signals without
having to stop at a red?
signals on city arterial roadways are generally synchronized
or co-ordinated to minimize stops and delays on the
arterial roadways. In other words, the City tries to provide a
smooth movement of the traffic through groups of signals on an
arterial street. The degree or quality of traffic signal co-ordination
is influenced by a number of factors including such things as the
spacing of the signals along the street, the prevailing speed of
traffic on the street, and the traffic signal cycle length.
The goal of signal co-ordination is to get the greatest number
of vehicles through the system with the fewest stops in a comfortable
manner. It would be ideal if every vehicle entering the system
could proceed through the system without stopping. This is not
possible, even in well-spaced, well-designed systems. Therefore,
in traffic co-ordination, the majority rules, and the busiest traffic
movements are given precedence over the smaller traffic movements.
who wait to enter a major street from a side street, often ask
have to wait so long for a signal to change,
especially when no traffic can be seen on the larger street. To
allow for co-ordination on the larger street, the side street traffic
must wait until the main traffic movement on the larger street
has gone through the intersection. It is possible that the traffic
on the larger street can’t be seen immediately, but will
soon be passing through the intersection.
A total of 83% of our signals are controlled by a central computer,
which is called the Main Traffic Signal System (MTSS). MTSS provides
different timing plans for different times of day and allows Transportation
staff to monitor its operation.
More than 15%
of our signals are on the SCOOT system. SCOOT (Split, Cycle and
Optimization Technique) is a demand-responsive
Urban Traffic Control system. The system uses “loop vehicle
detectors” located on all approaches to the intersection.
The data produced by these detectors are processed by a central
co-ordinating computer, which may decide to alter the traffic signals
at an intersection. One of the features of SCOOT is that signal
timings are changed frequently (typically every phase or cycle)
and gradually (usually by only a few seconds at a time).
Other Traffic Control Devices
I have an all-way stop control installed at an intersection
in my community?
To determine whether the installation of an all-way stop
is warranted, Transportation staff must first conduct a traffic
study at the intersection. This study considers a number of key
factors such as collisions, traffic volumes, roadway geometry
and neighbouring traffic control devices. If the requirements
are met, staff will typically recommend the installation of an
all-way stop. Then, the local Community Council must approve
A few key points:
stop controls operate more effectively at intersections with
traffic volumes, and a balanced split between the traffic
on the major street and on the minor street.
stops are intended to control right-of-way and are not intended
How can I have a 40 km/h speed zone installed on my street?
Before the city considers implementing a 40 km/h speed zone
on a given street(s), within a community, Transportation Services
staff first conducts a speed study to determine the volume of traffic
on the street as well as the prevailing vehicle speeds. The study
looks at a number of factors including operating speed, collisions,
roadway geometry, adjacent land uses and pedestrian activity. If
the requirements are met, staff will typically recommend the change
which must then be approved by the local Community Council.
40 km/h speed limits are typically posted on local and collector
roads in front of schools, or if the road is constructed in such
as way that would require motorists to reduce their speed.
be done to improve the safety and efficiency in front of school
when parents are picking up and dropping off their children?
in front of most schools can be chaotic during school admission and
dismissal. Transportation Services staff work with
staff from the school, the Toronto Police Service and concerned
parents to improve this situation through education, enforcement
or adjustment to the parking regulations. There are also a number
of innovative programs available to assist with traffic management
in the vicinity of schools. Transportation Services staff will
investigate the concerns of residents and/or school staff to determine
what is the best way to improve the situation at the school.
What is “Traffic Calming”?
calming is a term most commonly associated with physical features
placed on a roadway to influence the speed of vehicles.
The most common form of traffic calming in the City of Toronto
is the speed hump.
There are many factors to be considered before traffic calming
devices are installed. One of the most important factors is the
support of the residents living on the street where the traffic
calming is being proposed. A petition showing support of residents
on the street is the first step toward having a traffic calming
device installed in a neighbourhood.
Traffic calming measures such as speed humps can have a positive
influence in reducing vehicle speeds. However, there are negative
effects associated with traffic calming including, increased noise,
decreased emergency vehicle response times, increased air pollution
and diversion of traffic to adjoining streets.