US Megacities – Growth and Road Safety

The world population is growing rapidly, especially in urban areas. According to the United Nations, about 29% of the population lived in urban areas in 1950.

In 2011, that number nearly doubled to 52% and is expected to grow to almost 70% by 2050.


Megacity Population Growth over Time

Growth is most noticeable and significant in the larger cities across the world. These cities are referred to as megacities and have a population of over 10 million.

To give some perspective of this rapid growth, in 1970, there were two megacities in the world, Tokyo and New York. By 2011, almost 10% of the world’s urban population lived in one of 23 megacities, spanning five continents.

By 2025, it’s predicted there will be 37 megacities, which would encompass 14% of the world’s urban population and 8% of the total population.


These are the megacities (population of 10 million+) across the world as of 2011. It is expected to grow to 37 cities in 2025.


US Megacities Report for Road Safety

This type of population data is imperative for planning infrastructure, understanding future trends, and determining road safety.

A recent report by the University of Michigan Transportation Research Institute entitled, Road Safety in New York and Los Angeles, compares the road safety of the United States’ two megacities, New York City and Los Angeles, against the rest of the nation.

The report, released in September 2012, measures various demographics as well as crash statistics including:

  • Crash type: fatal vs. all crashes, number of vehicles, person type (driver, passenger, pedestrian, etc.)
  • Demographics: gender, age
  • External conditions: weather, road surface, lighting conditions
  • Location: roadway alignment, road type
  • Driver variables: speed, alcohol use, avoidance maneuver
  • Timing: day of week, time of day

For the report or all of the data for each of the above statistics, view the report in its entirety.



US Megacities Report for Road Safety – Conclusions

The crash rates (fatal and non-fatal) vary greatly between the megacities and the rest of the US. There are proportionally more crashes in each of the two megacities than in comparison to the entire US.

Based on the measurements for the above statistics, researchers found the following of crashes that occur in a megacity:

Crash Type:

  • More multi-vehicle crashes, more fatal multi-vehicle crashes, more fatal crashes with non-fixed object. The researchers state this could mean that these types of crashes have more severe consequences.
  • More fatal crashes involving only one vehicle (especially in New York)
  • Less head-on crashes (especially in New York)
  • More pedestrian and cyclist fatalities (especially in New York)


  • Less fatal crashes with more than one fatality
  • More male drivers in crashes (especially in New York)
  • More males  in  fatal crashes (only in New York)

External Conditions:

  • Less crashes (including fatal) in rain or wet roads (only in Los Angeles)
  • More crashes (including fatal) in rain or wet roads (only New York)
  • Less crashes on (including fatal) at night on unlit roads
  • More crashes on (including fatal) at night on lit roads


  • Less fatal crashes on curves
  • More fatal crashes on divided highways
  • More fatal crashes on one-way roadways (only in New York)
  • More fatal crashes on entrance/exit ramps (only in Los Angeles)
  • More fatal crashes at intersections and low-speed roads (especially in New York)


  • More crashes on Saturdays, but fewer fatal crashes
  • More crashes and fatal crashes at night

Due to the increased population in megacities vs. other urban cities, crash factors and statistics are quite different in comparison. These results are important for understanding the factors that can attribute to higher crash rates, especially fatal crashes.

Likewise, this data can be applied to infrastructure planning, building and expansion, as well as establishing safety regulations in urban areas including megacities.

Part of understanding the needs of a given roadway or traffic network requires completing various traffic studies that provide data on the traffic volumes, movements and routes travelled.

Miovision has flexible solutions for acquiring accurate, auditable traffic data whether you collect in-house or outsource it. For more information, contact us or sign up for one of our educational webinars.