Transportation Demand Management
Transportation Demand Management (TDM) Background
Transportation Demand Management (TDM) is the use of strategies to maximize the efficiency of our transportation systems – leading to improved mobility, reduced congestion, and lower carbon emissions. TDM aims to provide all people with transportation options that enable them to travel from their location to a destination in an affordable, efficient, and sustainable way.
The City of Madison adopted a TDM Ordinance in 2022, requiring development within the city to consider and implement TDM strategies. By requiring new development, changes of use, and site alterations to implement TDM strategies, the City can better align with adopted policies and plans aiming to increase investment in transit, bike, and walking amenities and infrastructure.
Complementing the TDM Ordinance is the TDM Program, which provides background information and data on TDM, case studies of municipalities with established TDM Ordinances, details on TDM requirement thresholds (i.e. how the scale of a project impacts the TDM points required), and TDM strategies/measures to implement. Applicants looking to receive project approval choose from a variety of TDM-related measures, suiting the needs of their site and use(s). Examples of measures within the TDM Program include:
- Locating housing near transit routes
- Offering free/subsidized transit passes
- Unbundling parking from rental leases
- Installing a bike share station
- Constructing an accessible bus shelter
- Establishing an Emergency Ride Home Program
Need for a TDM Ordinance in Madison
According to the most recent American Community Survey data available, roughly 55% of Madison's work-related trips were in the form of drive-alone trips. The share of work-related drive-alone trips have significantly decreased since the onset of the COVID-19 pandemic (64% in 2019 to 55% 2022), largely due to a substantial increase in people working from home (6% in 2019 to 20% in 2022).
The dramatic shift in commuting behavior presents an opportunity for Madison to continue the trend of decreasing the share of people driving alone. Driving alone greatly contributes to traffic congestion and greenhouse gas emissions, and is more costly and less efficient than other modes of transportation. The lower the percentage of people driving alone, the more efficiently transportation systems operate.
Though the share of drive-alone trips has decreased since 2019, the City of Madison population continues to increase and outpace projections. The TDM Ordinance can help new housing and jobs in the city to promote all modes of transportation – de-prioritizing drive-alone trips. Madison cannot accommodate future transportation demand growth resulting from population increases if drive-alone trips also increase. The city has limited opportunities to add capacity to major arterials, which would be necessary with increases in population and the share of drive-alone trips. Putting car-centric infrastructure as the top priority for accommodating population growth carries significant risks. Increased congestion, higher infrastructure maintenance costs, more crashes, and higher greenhouse gas emissions, could occur if the city does not grow its share of public transit, biking, carpooling, and walking trips, as part of accounting for population growth.
Implementing a TDM Ordinance is a recommendation in several adopted City plans, including the Imagine Madison Comprehensive Plan, Climate Forward Vision, and Madison in Motion. While playing a small role in the development review process, the TDM Ordinance has a direct impact on how development impacts the city’s overall transportation system.