Carpenter said about 4,400 trips occurred on the West Valley extension on Monday, bringing it closer to the 5,000 daily trips that officials estimated that line would have at its opening.
On the new Mid-Jordan line from the Daybreak area of South Jordan, it had about 6,200 trips still well below the 9,000 that officials had predicted at its opening.
Carpenter noted that ridership on the new TRAX extensions has increased by about 16 percent in the two weeks that they have been opened.
"People don't change their commuting patterns overnight so we expect these numbers to gradually increase over the next three to six months as people try out the system," he said. "It will take several months for it to settle into what we consider opening numbers."
Carpenter added that while the West Valley extension is coming close to projections, "on the Mid-Jordan we are low and probably will continue to remain low. ... [Housing] development along the line hasn't advanced as quickly as anticipated when we were modeling the ridership."
Still, some new park-and-ride lots are filling with the return of the U. students.
For example, Carpenter said the West Valley Central station parking lot "was at more than 100 percent occupancy." He said its 150 stalls have been filled this week, plus 25 to 30 cars on the street there.
Carpenter suggests that people not arriving early enough to find parking at the West Valley station may consider driving about a mile farther to the Decker Lake station near the Maverik Center. "We have shared parking with the Maverik Center. We have 700 stalls there across the street from the station." He said it has only been 2 percent full.
Carpenter said nine different bus lines also connect with the West Valley Central station, so people may want to consider taking the bus to TRAX instead of driving.
Some other new lots are heavily used, but not quite full. For example, he said the 4800 South station park-and-ride on the Mid-Jordan extension has been 91 percent full, and the 2700 South station has been 77 percent full. But he said the Jordan Valley station between them has been only 16 percent full.
That is probably because UTA announced that it plans to charge $2 a day for parking at Jordan Valley. However, Carpenter said UTA decided to waive that parking fee for the first 90 days to allow commuters to try the parking there for free.
Also, Carpenter said the Courthouse Station platform has been crowded as people use it as a transfer point to catch red line trains to the University of Utah. He said UTA encourages riders coming from the south to transfer at one of several other stations shared by all lines with the red line, and not wait until reaching Courthouse.
"If you are coming from Sandy, you can transfer anywhere between 6400 South and Courthouse. If you are coming from West Valley City, you can transfer to a red line anywhere between 2100 South and Courthouse," he said. "People will naturally figure that out over time." Also, he said UTA plans to remove some large planters on the Courthouse station to make more room for people there.
Carpenter said TRAX has been having trouble meeting its schedules the past couple weeks. One problem, he said, is more trains are sharing tracks, so when one has a problem it can cause delays throughout a more complicated system.
He said new TRAX cars also had a software problem that caused several to lose propulsion, and block tracks for other trains. He said UTA is working with the manufacturer to solve the problem.
Also, he said several vehicle accidents not involving TRAX trains have blocked tracks. For example on Tuesday, a car accident at 400 South and Main in downtown Salt Lake City blocked all trains on all lines in both directions for about a half hour, he said.
Finally, he said big crowds on platforms such as Courthouse Station have caused delays as they try to move onto trains, or the handicapped use ramps amid the crowds. He said that is one reason UTA urges riders to use other stations for transfers, which should help trains keep closer to schedule.