Nelson\Nygaard specializes in managing transportation demand. To us, transportation demand management means comprehensive planning aimed at changing the status quo dependence on the automobile. The following explains 20 principles that guide our transportation demand management planning work.

Managing Demand is as Important as Managing Supply
Instead of asking, "How many more roadway lanes are needed to accommodate 20,000 more residents?" TDM asks, "How can we 'fit' 20,000 new travelers into the existing roadway capacity?" Managing demand makes the best use of supply by maximizing unused capacity through pricing, incentive, time-based, and capacity strategies.


Personal Access is Prioritized Over Vehicular Access
TDM emphasizes personal access rather than vehicular mobility -- that is, how can people access the goods, services and employment they need, rather than how do we make sure they can drive to these things? Transportation, after all, is not an end in itself but a means to an end.


There is Limited Travelway Capacity
TDM strives to treat roadway, bus and sidewalk capacity as valuable, limited assets to be carefully managed. TDM maximizes the use of roadways by spreading the peak travel hours. TDM speeds travelers through the network with traffic signal timing and timed transfers. TDM rewards efficient consumers with HOV bypasses and discounted transit passes. TDM develops new services like improved transit routing.


TDM is More than "Ridesharing"
TDM strategies go beyond increasing vehicle occupancy and can range from simple marketing programs to complex land use and pricing strategies.


It's About Land-Use
Land-use patterns are often the most critical factors influencing travel mode. Replacing vehicle trips with proximity is critical to low single-occupant automobile usage. In-fill housing strategies and mixed-use development strategies are TDM strategies. Similarly, creating a pedestrian or bicycle-friendly environment is dependent upon design criteria, zoning and urban landscaping. Finally, effective transit depends upon density and the number of people that can be served within a quarter mile of a transit route.


Traffic Congestion Negatively Impacts Community Livability
The negative aspects of vehicles include noise, delays, air and water pollution, driver stress, residential stress, and reduced mobility. Travel conflicts include competition for roadway space between buses and cars, cars and bikes, or bikes and pedestrians, as well as on-street parking versus retail parking.


Vehicle Use Is Not Evil
Using roadways to their maximum capacity makes the best use of this valuable public resource. Cars on the road also means that people are moving about, buying goods and services and pumping dollars into the economy. The trick is being able to do this without negatively impacting community livability. TDM is not intended to, nor can it, make traffic disappear. Rather TDM is intended to mitigate the negative aspects of traffic congestion by providing people with travel choices.


It is Often More Cost-Effective to Better Manage Existing Resources than to Add More Capacity
The first strategies that should be examined are those that seek to make better use of existing carpool lanes, existing informational programs, transit resources and parking supply. Beyond this, strategies that add capacity -- like financing additional transit service or building additional bicycle lanes - should be addressed.


Know and Segment the Market
The most effective TDM strategies are those that are targeted toward specific traveler markets. Identify the numbers of people who live within a quarter mile of local transit routes, three miles of long-distance commuter rail stations, or along convenient bikeways. Understand how many peak trips are generated by in-bound and out-bound commute traffic, school trips, shopping trips and other trips.


No Single Solution Works for Everyone
TDM is about providing people with more transportation options to choose from and leveling the economic playing field between those choices. It is not about "forcing" people to do one thing or another. The modern American transportation system, however, often provides travelers with only one viable "choice": driving alone. TDM seeks to broaden the choices.


Information is Critical to Change because Inertia is a Powerful Force
People must be informed about their transportation choices in order to make changes. People become used to the mode they use most often. They become comfortable with the advantages and disadvantages of that mode, whether it is traffic congestion or the occasional late bus. Easy-to-obtain, and easy-to-understand information about alternatives, as well as incentive programs to encourage change, are vital to overcoming this inertia.


Travelers are Rational Decision-Makers
Travelers are transportation consumers, and they look for the best value for their needs. A traveler will not select a transportation mode if it is more time consuming, less convenient, less reliable and equally costly.


Time is the Most Critical Factor Influencing Mode Choice
The time it takes to use a particular mode is the most important factor a traveler considers. Travel time depends upon the distance between destinations, traffic conditions, and the available transportation infrastructure.


Other Factors Also Influence Mode Choice
Convenience: access at the starting and ending points; related benefits such as the ability to carry packages (driving) or the ability to read while traveling (transit).
Reliability: knowing that the mode will be on time and consistent
Customer Service and Dignity: does using the mode make a person feel more or less frustrated, stressed, or valuable?
Cost
Flexibility: Bicycles, walking and the personal automobile have the most flexibility. The more frequent transit, the more flexible it is.


Mode Choice Is Influenced by Parking Availability, Parking Price, and the Availability of Travel Choices

The amount of parking demand depends upon the available options to driving, the amount of parking supplies and the price of parking. The greater the travel options, the more parking demand drops in response to parking price increases. The greater the price of parking, the more demand there will be for the alternatives to driving alone.


Shifting Each Additional Trip Becomes Increasingly Challenging

Even when a community puts little effort into TDM, people will use alternatives since no singe solution, including driving, works for everyone. As TDM effort increases, the people who can most easily switch modes will do so first. To continue mode shift, TDM programs must become more robust, and often more costly. Not only is each new trip more costly to shift from driving, but the additional cost of the benefit often must to be applied to trips that were already shifted.


TDM Focuses on Peak Hour Trips
The maximum demand placed on the transportation network generally occurs during commute hours. As a result, if the commute demand can be managed, the system capacity will meet travelers' needs.


It is More Difficult to Shift Non-Commute Trips … But TDM Strategies Can Influence All Trips
Non-commute trips often occur with no set pattern (limiting traditional carpooling), in "alternative modes" (carpools of family or friends, often involve transporting packages (increasing barriers to bicycling or walking) or involve making several stops (limiting transit use). TDM strategies that address the transportation system and the built environment impact all trips. These strategies include increasing transit frequencies and service, improving the bicycling and walking environment, increasing mixed-use development and increasing densities.


Sometimes "Inside the Box" is More Effective than "Outside the Box"
Strategies that are new and creative or that employ new and expensive technology are not always the most effective strategies. Knowing the market allows us to determine if a moving people sidewalk or free electric bike program will work better than a parking fee or increased transit service.


There is No Magic Bullet!
Travel mode is influenced by complex daily life patterns. Changing travel patterns often requires a long-term approach to the economics of transportation, the transportation infrastructure, and the form of our built environment.