Travel Demand Management > Ridematching                             Printer-friendly version

What Is It?

• Ridematching facilitates ridesharing (carpooling or vanpooling) by helping travelers find others with similar origins, destinations and travel times who are also interested in carpooling for regular or non-recurrent trips. Users access this information from the Internet, intranets and office computers, home computers, interactive telephones and pagers.

• Ridematching can be planned and executed on a daily or weekly basis for regular commute trips that are fairly consistent and do not change. Alternatively, ridematching can be dynamic such that an independent organization matches passengers with drivers for individual ad-hoc trips (as opposed to regularly scheduled trips), using telephone and computer technologies.

• The emphasis of ITS ride matching systems is on dynamic ridesharing, although they also offer more long term services. This is achieved by automatically generating ride match lists upon request by interested parties via the web, intranets or automated telephone service.

Key Results

The first dynamic ridematching projects, the Bellevue Smart Traveler and Los Angeles Smart Traveler, generated very low levels of matches. Participants were amenable to the dynamic ridesharing idea, liked the technology and presentation of information, but were unwilling or unable to form rides for a variety of reasons. Ridematching systems were initially limited by several factors including:

• The participant base was often too small to ensure sufficient matches.
• Projects were implemented a little before the real boom in Internet use.
• Technologies available at the time for developing dynamic ridematching systems were somewhat cumbersome.
• Initial projects may have been viewed by some potential users as too temporary or too experimental.
• Insufficient incentives to help promote ridesharing such as HOV lanes, parking incentives, and other techniques to encourage carpooling.
• Safety concerns: commuters were often reluctant to travel with strangers.

More recent dynamic ridematching projects, such as the Seattle Smart Traveler (SST), generated match and carpool levels that approximated the numbers of traditional rideshare programs. In fact, the SST was operated in parallel to a traditional, regional rideshare system for one year and the two systems were marketed to the user community on a side-by-side basis. The SST and the traditional system acquired approximately the same number of users, although there was little overlap in the user populations using the parallel systems. The project thus demonstrated that there was a user population (not reached by traditional methods) that could be reached using the Internet for dynamic ridesharing services.

As use of the Internet increases rapidly, new communication devices proliferate and congestion worsens, use of ridematching services could grow beyond the numbers achieved by traditional rideshare programs.

Potential travel impacts

Ridematching has travel impacts to the extent that it encourages ridesharing. Rideshare programs which include incentives (reserved parking and HOV lanes) often reduce commute trips by at least 10% (Winters and Rudge, 1995). If implemented without such incentives travel impacts are often smaller. The most effective programs tend to have paid parking, subsidies for transit, and other incentives to encourage reduced automobile commuting.

Because rideshare passengers tend to have relatively long commutes, mileage reductions can be relatively large. For example, if ridesharing reduces 5% of commute trips it may reduce 7% of vehicle miles because the trips that are reduced are longer than average commutes. Rideshare programs can typically reduce up to 8.3% of commute VMT, up to 3.6% of total regional VMT, and up to 1.8% of regional vehicle trips (Apogee, 1994; TDM Resource Center, 1996).

• Congestion Reduction : Reduces peak-period automobile travel.
• Road & Parking Savings : Reduces peak-period automobile travel.
• Provides consumer savings.
• Increases travel choice.
• Environmental Protection : Reduces automobile travel.
• Community Livability : Reduces automobile trips.

Costs

Costs include the development of ridematching systems (software, phone systems) as well as program administration expenses. The Los Angeles Smart Traveler project was estimated to incur $150,000 in setup and marketing expenses. If the costs are assumed to be sunk costs, this amounts to an average of $3 per phone call received in operating costs (Guiliano, Hall and Golob, 1995). As the costs of developing new communications systems has decreased in recent years, presently, system development costs are likely to be lower.

Costs to participants include additional travel and time needed to meet rideshare partners, schedule constraints needed to match commuting times, loss of privacy, and restrictions on stops for errands.

Implementation challenges

The main challenges are:

• Lack of appropriate incentives to help promote ridesharing (HOV lanes, parking incentives etc.)
• Reluctance of potential carpoolers to travel with strangers: a ridematching system that had a security screening process might help address this issue.
• Lack of marketing: potential users need to be informed of this option.

Where is it implemented?

• Bellevue Smart Traveler
• Los Angeles (Commuter Transportation Services)
• Los Angeles Smart Traveler
• Metro Vanpooling Program
• Minerva Dynamic Ridesharing Service
• Redmond Ride Sharing
• Seattle Smart Traveler

Author: Dimitri Loukakos