The impact of a new rail line, branch or extension on a system's unlinked trip count depends upon many factors. In general terms, the implementation of rail systems should generate new unlinked trips because they tend by nature to draw new customers, including suburban men, out of their cars. This is especially true when parking fees in the CBD are high. Links can be lost however, when rail route design allows former bus riders to save one or more transfers previously made on their commute. CTA's Orange line (running diagonally across the grid SW from the Chicago's Loop) which opened 10/31/93, was a bonanza for Pace suburban bus ridership for routes connecting to CTA at Midway airport. The line exceeded CTA ridership expectations in part due to high suburban ridership, but also resulted in some lost linked trips (not individuals) between bus routes - and of course a substantial shift from bus to rail. Limited stop express services can add individuals overall but eliminate the need for some transfers when they cross over route ends. The X49 for example, eliminated some transfers (unlinked trips) between routes 49A and 49, however ridership increases and customer satisfaction rose far more than trips lost. In Chicago, it is more likely that increases in off-peak discretionary riding by electronic pass users (30 and 7 day rolling pass markets have grown substantially since the were re-introduced in the Winter of 1998) are responsible for a portion of this shift. New York of course had tremendous ridership growth when the eliminated the 2nd fare required to move from bus to rail when their Metro Card was used. Check with them, but my guess would be that they have also had big boosts in off-peak riding, etc stimulated by having pre-paid media available. DC's Smart Card probably generates many new rides as well. Could the impact of just these 3 systems be enough to cause an increase in trips with no new net gain in riders? Once you have a farecard, even a money card rather than a pass, you are much more inclined to hop on a bus or train to take a trip. Discounting and the impact of lowered average fares on ridership through the use of these fare instruments may also be a factor. The issue of whether census data questions are complete enough to extract true mode splits (raised in another thread) is a valid one, especially when respondents are asked about an entire previous week is a valid one. BUT, I also think that it is unrealistic to expect more from the Census that can reasonably be expected. Reconfiguration of a rail line can cause losses. When the Dan Ryan/Lake and Howard/Englewood/Jackson Park were realigned 2/1993 to connect the busy South and North branches in the Red Line and less busy South and West branches as the Green Line many transfers which had been recorded as unlinked trips were eliminated with no real reduction in persons (average trip lengths expanded). Reconstruction of a rail line can also cause losses. The decision to close the Green line for reconstruction rather than single track in 1/1994 resulted in bus and offset gains made by the new Orange Line rail. The impacts of service changes are often complex. It likely that changes in auto ownership and transit riding frequency among fairly frequent customers over the decade are also an important of the story. It is also very difficult to make assessments of persons using a system from unlinked trip counts. This is part of why NTD average trip length calculations and passenger miles estimations are important. Peter J. Foote PFoote(a)TransitChicago.com Market Research/Resource Planning Planning Division Chicago Transit Authority 120 N. Racine Avenue Chicago, IL 60607 (312) 733-7000 x 6840 (Voice) (312) 432 - 7108 (Fax) **************************************************************************** **************************************************************************** ******************************************* Unless otherwise stated, the views expressed are those of the author and not those of the Chicago Transit Authority. **************************************************************************** **************************************************************************** ******************************************* http://www.TransitChicago.com CTA CUSTOMER SERVICE HOTLINE 1-888-YOUR-CTA RTA Travel Information 836-7000 ----- Original Message ----- From: "Mark Schlappi" <Schlappi(a)mag.maricopa.gov> To: "'Chuck Purvis'" <CPurvis(a)mtc.ca.gov>ov>; <ctpp-news(a)chrispy.net> Sent: Wednesday, July 03, 2002 6:01 PM Subject: RE: [CTPP] Reconciling Census Transit Commuters with Ridership Statistics have the (On 2000. APTA in transportation living" (in 40 which level, or the