Introducing Actionfigure® Foresight - Understand how real people use transportation. Make better real estate decisions.​

TDM 101: The history and future of Transportation Demand Management

Since we first started writing about transportation demand management (TDM), a lot has been changing. More cities are requiring developers to make new buildings more TDM-friendly. Other cities are making employers take actionable steps to get their employees to change the way they are getting to work. Whichever group is being tasked with making the most change, the goal is the same – keep people from driving alone.

Feature image for TDM 101 past, present, future of transportation demand management

Transportation demand management

If you keep up with city planning initiatives, you’re likely already familiar with TDM. To get everyone on the same page, let’s run through a quick refresher.

TDM is a set of strategies to encourage the use of alternative forms of transit to get around instead of driving alone. There’s a fine line between TDM efforts and improvement to infrastructure. While a new bike lane might seem like a TDM effort, that’s really an improvement to infrastructure because it involves effort from the city. Installing a shower at the office for employees to use after biking or walking to work, on the other hand, is TDM, because employers can do so without any outside intervention.

Now that everyone’s caught up, let’s dive into the changes going on in the world of TDM over the past few years.

Start here


With the inception of its 1991 Commute Trip Reduction Law, Seattle has truly been making the effort to keep residents from drive alone. This law requires employers with 100 or more employees, working at a single site between 6 and 9 a.m., to meet a certain number of TDM requirements. As part of the law, companies must:

  • Appoint an Employee Transportation Coordinator 
  • Work with the city to assist in the implementation and administration of the CTR program
  • Conduct a commuter survey once every two years to monitor their employees’ drive-alone rates
  • Distribute information about the program to employees twice a year and inform every new employee of the company’s CTR goals
  • Implement measures such as offering subsidized transit passes, providing real-time transit information, allowing flexible work hours, and more.

To say this law has made a positive impact on the city’s drive-alone rate would be an understatement, especially in recent years. Between 2010 and 2017, Seattle added nearly 60,000 jobs downtown, while decreasing the drive-alone rate to just more than 25 percent.

San Francisco

While Seattle puts most of the TDM burden on employers, San Francisco challenges their developers to make the difference. In order to get a new project approved, developers must submit a TDM plan at the beginning of the planning process. Submitting a TDM plan is included in the SHIFT initiative, which is a component of the city’s Transportation Sustainability Program. The goal of SHIFT is quite literally get residents to shift away from driving alone. 

Each new development must hit a given point total in order for the project to be approved. These point totals – depending on the size and use of the development – dictate how many separate TDM features need to be included in a new development. San Francisco has laid out a menu of options with corresponding point totals, allowing developers to mix and match depending on which ones make the most sense for their property. The greater the impact a feature makes or the more effort it requires, the more points the developer can get for it. Some of the options are adding bike parking, improving walking conditions, providing on-site childcare, and many more.

Cambridge, MA

Cambridge, MA, is another city putting the burden of lowering drive-alone rates on the shoulders of its developers. Whereas San Francisco’s requirements are largely based on use and square footage, Cambridge bases its on the number of parking spots available at a development. Cambridge made its Parking and Transportation Demand Management Ordinance (PTDM) permanent for developers in 2006.

There are two levels of requirements for new buildings. If a non-residential development has between five and 19 parking spaces, a Small Project Plan must be submitted. This plan requires at least three TDM measures, which can be a shower for bike commuters, a free shuttle service, or a variety of different options listed by the city.

The second level is a Large Project PTDM Plan, which is required for non-residential buildings with 20 or more parking spots. These properties must comply with the single-occupancy vehicle (SOV) commitment, offer a comprehensive set of TDM measures, and submit annual monitoring and reporting on what’s being done.

Who’s next?

While Seattle and San Francisco have their plans in place, Los Angeles is following suit and putting it all together. 

Los Angeles is a city known for major traffic and pollution issues, and they’re taking major steps to fix both. After the 2019 Paris Agreement, the city decided it needed to make a more aggressive plan for its residents. Being one of the highest polluting cities in the world is definitely a good reason to set a goal of net-zero carbon emissions by 2050, and TDM is the foundation of achieving this goal.

In July 2020, the city implemented designs and regulations to make certain areas more walkable, transit access more available, and developments greener. To help developers even more, the city is providing online access to a VMT calculator for them to plug in their plans and and see what the impact would be. Depending on whether their calculation passes the thresholds, developers could have to restructure their plans to meet requirements.

The who’s who of TDM

Although a lot of companies have TDM plans in place, either because of requirements or on their own accord, there are a few standouts who have gone above and beyond. 

The Golden State Warriors aren’t just one of the NBA’s best teams in the past decade, they’re one of the best teams of all time. To keep up with their success on the court, the organization is making a huge impact off the court when it comes to maximizing transit use. With a seating capacity of just over 18,000, there are only 900 parking spots at their new Chase Center. The Warriors needed to get creative to accommodate guests and employees, and they did not disappoint! How? Buy-in from all available agencies.

Boston University has more than 34,000 students and more than 10,000 total employees. In order to accommodate that amount of people coming and going from campus everyday, they help everyone leave their cars at home. For staff members who benefit the most from using public transit, the university pays for half of a monthly pass and parking. Staff members who carpool can save as much as 75 percent on a parking pass, priority parking, and a $50 gas card to alleviate some of the financial burden. One of our favorite benefits is for employees who bike to work. The university will reimburse staff members as much as $300 per year for bicycle-related purchases, as well as offering discounted bikeshare memberships.

What can be offered

There are a lot of measures that you can take to keep employees from driving alone. Installing a bike rack outside of your office is great and lets everyone know they can secure their bike during the workday, but no real change will come from doing just one thing! Real change comes when the level of commitment from the top is evident. Here are a few of our ways to encourage alternative commutes.

Indoor secure bike parking

Setting up an indoor space where your employees can be confident their bikes are secure will make a big difference.

Shuttle service

Not only do shuttles get more employees out from behind the wheel, they also have access to HOV lanes, which speeds up the trip. Providing onboard WiFi  even affords employees the opportunity to get work done during their commute.

Parking cash-out

If you really want to make sure your employees aren’t going to use parking spaces, pay them not to! Parking cash-out allows you to offer the same benefits to everyone by offering your non-driving employees a cash bonus equivalent to the value of the parking space.

Real-time transit information

Access to real-time information about public transit and other mobility options has been proven time and time again to make people more likely to both consider taking it and to do so on a consistent basis. Make sure employees have this info easily available in the office lobby and on their phones!


While TDM is still a growing initiative in most cities, it’s important to keep in mind that it’s not a one-and-done effort, but rather an ongoing push. Seattle has seen great results, but the city as a whole has been working toward these achievements since 1991! Adding indoor bike parking is a great start, but it’s important to constantly improve, add, and upgrade your TDM efforts.

Latest Posts