Moving Atlanta's Traffic Forward

We know that the length of our drive to work has a huge impact on our life satisfaction.

Every week we waste precious hours of our lives sitting in endless traffic jams, getting more stressed by the minute.

So can we truly "fix" our traffic?

There's a lot of good news there, and some of it is counterintuitive, so buckle up!

Let's start with what we know isn't going to work.

The Ghosts of Traffic Past & Future

Only focusing on expanding roads.

We know that adding lanes doesn't ease congestion for long, if at all. Around the country we see metro regions endlessly trying to expand their roads without success.

Don't we have to expand roads because of population growth?

Between 1993 and 2017, we increased the number of lane-miles by 42% in our largest cities, even though the population only increased by 32%. The result? Congestion increased by 144%!

The video below is a great explainer for this concept.
Autonomous vehicles

When these finally hit the road, it's going to take a decade, or more, before we see enough being built to have any potential impact. Until then, they'll sit in regular traffic surrounded by humans driving… well …humanly.

Additionally, when vehicles are fully autonomous, we'll send them out more for errands, grocery pick up, etc., further increasing the number of vehicles on the road at any given time.

So what does work?!

This One(+) Weird Trick to Solve Traffic!

HOW we design roads is often more important than how large they are!

NYC found, for instance, that reconfiguring their traffic flows and adding bike lanes actually improved travel time for cars. And reduced pedestrian and cyclists injuries and death as well!

At first this seems counterintuitive, right? If we remove a lane for bikes or buses, won't the remaining lanes be more congested?

The key is the rate of flow. One lane moving consistently moves more cars than two lanes stuck in a traffic jam.

Take this oversimplified example:

Before: 4 lanes inefficiently used

After: 3 lanes optimized for traffic flow, w/ bike lanes to further reduce # of cars on road

There are so many similar design tweaks that can make an astounding difference to the rate of flow!
Building a variety of transit options can reduce congestion

Look around in the next traffic jam you're in. In Atlanta, you're likely to see around 77% of the cars only have one person in them. That's a lot of space and fuel needed to move one person around!

Cars: 600 - 1,600

Buses: 4,000 - 8,000

Train: 10,000 - 25,000

Bikes: 7,500

Transportation Type: People per Hour

Data Source: NACTO

A car can be one of the most inefficient ways to get a lot of people through the city. For some they are necessary or preferable though. Making sure we have a variety of reliable travel options benefits everyone!

This only works if enough people switch to the alternate modes

Very true! Fortunately there is already a demand for more varied, complete and safe options! And demand increases in cities that they modernize their infrastructure.

Setting aside lanes in dense population areas for a bus lane or bike lanes, intuitively feels like it will be worse for cars. But as modern metro areas are discovering, it can be a win for everyone.

Some folks have hang-ups about certain transportation options like cycling, buses, rail, etc. Sometimes these modes get tangled up in our notions about freedom, poverty, elitism, etc. This is worth some introspection! The stigmas we accept tend to not reflect reality. Give one a try! Hop on a bike or a bus with an open mind, and see if it challenges your expectations.
Car crashes snarl traffic, and we can reduce them!

In Georgia, 76% of crashes are caused by behaviors like distractions, impairment or driving too fast.

We treat crashes as an unavoidable fact of life. We know it only takes a small mistake to create a ton of damage, even to the point of injury or death.

But crashes aren't unavoidable! In regions that have had success in reducing crashes, they create what is often called "forgiving infrastructure". It's the idea that we should build infrastructure that accounts for the fact that we all make mistakes.

A couple of examples:
1. Lowering Speed Limits
  
  Suggesting this to an ATL commuter should typically only be done if you have access to private security!
  
  But counterintuitively, it gets us to our destinations faster on average. A reduction in only 5mph can reduce crashes by nearly 50%.
  
  And more people get to their destination alive.
2. Traffic Calming
  
  In some areas we can make adjustments to roads that allow cars to travel at safe reasonable speeds, but make them difficult to race on. This can be adding things like speed tables (speed bumps are so last century), putting slight curves in roads, narrowing lanes, etc.
This list could go on, with things like preventing right turns on red, or making pedestrian crossings safer, or automated speed enforcement (not privately-run!) in high crash areas and school zones, or protecting bike lanes.

Every road needs a different set of solutions. But each can be effective in different contexts in creating safer roads with fewer crashes.

Conclusion