Princeton University’s Goal
The Princeton University Sustainability Report sets the University goal of a reduction of 500 vehicles by 2020 in conjunction with these five principles:
1. Maintain a pedestrian-oriented campus
2. Preserve the park-like character of the campus
3. Maintain campus neighborhoods while promoting a sense of community
4. Build in an environmentally responsible manner
5. Sustain strong community relations

TDM Strategies for Implementation
• Promote walking and biking as means of transportation to and on campus
• Encourage use of public mass transit to campus
• Develop and promote car and vanpools
• Improve and integrate on-campus transit system (TigerTransit)
• Explore telecommuting and flex time programs
• Communicate TDM programs to the campus community with incentives for participation
• Institute new vehicle registration program for faculty, staff and students parking on campus

TDM at Princeton University
• Biking/Walking
• Guaranteed Ride Home (See Below)
• Rideshare Carpool Service
• Vanpools

Guaranteed Ride Home
This program provides an occasional ride home to commuters who use alternative modes of transportation to work. The program is subsidized through the employer, free of charge to the users. Guaranteed Ride Home program typically limits the amount of rides home per year.

Background
TDM stands for Transportation Demand Management and is a series of measures promoting alternatives to SOV’s (single occupancy vehicles) to reduce traffic congestion and improve air quality by maximizing the use of existing infrastructure. These measures include carpooling, vanpooling, transit, walking, biking, telecommuting and compressed work weeks.

This term originated in the United States and is linked to the economic impacts which occurred during the sharp increases of oil prices in the 1970’s. Long lines at gas stations soon proved the inefficiencies of single occupancy vehicles; and therefore, alternatives to driving alone were introduced. Although the term TDM originated in the United States, the concepts reflect mainstream transportation planning in Europe.

TDM applications in the past have been unsuccessful in America due to low and stable gas prices throughout the 80’s and 90’s. Low fuel prices have lead to an ever increasing amount of car ownership and vehicle miles traveled. The side effects to this trend have been rush hours delays, bottlenecks, deterioration of roadways and air pollution.