Despite adding hundreds of miles of transit service across Southern California in the last 25 years, the region continues to see ridership slip, and the reason may have a lot to do with cars.   Car ownership across the region — a six-county swath home to 18.8 million people — increased significantly among residents who have traditionally been frequent users of public transit, according to the study Falling Transit Ridership: California and Southern California. The study was commissioned by the Southern California Association of Governments, which includes Los Angeles, Riverside, San Bernardino, Ventura, Orange and Imperial counties. It did not include San Diego County.   The number of households in the region without a car — generally regarded as low-income families — fell 30 percent from 2000 to 2015, according to the study, conducted by the University of California Los Angeles Institute of Transportation Studies. Meanwhile, car ownership among immigrant households from Mexico, another traditional user of mass transit, increased. The number of immigrant families without a car in Southern California dropped 66 percent from 2000 to 2015.   The rise of car-ownership — particularly among populations that have not always had access to a vehicle — is what Hasan Ikhrata, executive director of the Southern California Association of Governments (SCAG), calls “the smoking gun.”   “The ‘smoking gun' is between 2000 and 2015 we grew as a region by 2.3 million people. And in the same period we added 2.1 million cars. That’s four times the rate from the 1990s,” Ikhrata pointed out.   Since 1990, the SCAG region added more than 530 miles of commuter rail and more than 100 miles of light and heavy rail. Despite this significant buildout of transit service, the region actually lost 72 million transit rides annually between 2012 to 2016.    At L.A. Metro, the region’s largest provider of mass transit, bus ridership fell 23 percent between 2009 to 2017, according to L.A. Metro ridership statistics. Meanwhile ridership on Metro’s light rail network increased 22 percent during the same period, a result partly due to expansions in the network. However, ridership was still down 14.2 percent systemwide during this period because buses remained the “workhorses” of Los Angeles mass transit.   Passenger miles on the rail system — an indication of distance traveled and trains in operation — grew to more than 700 million miles in 2017, a 28 percent increase over 2009. Passenger miles on the L.A. Metro bus system grew to more than 1.5 billion in 2012. By 2017, passenger miles were down to 1.2 billion.    L.A. Metro makes service adjustments twice a year "to improve existing bus service and to take a look at non-productive bus lines and service," said Rick Jager, a spokesman for L.A. Metro. Also, as new light rail lines are added, Metro pulls back bus service that may be duplicative.    Metrolink, a commuter rail service linking Los Angeles, Ventura, Orange, San Bernardino and Riverside counties, has seen annual ridership dip and rise over the last decade. In the 2007-08 fiscal year ridership reached nearly 12.7 million passengers. By the 2015-16 fiscal year, the number of annual passengers had slipped to 11.5 million, while total train miles increased 10.7 percent during this period, according to Metrolink statistics.   Granted, transit agencies would like to turn these statistics around. And the solution, researchers say, lies in getting more residents to choose transit, even if it’s only a few rides a month. The SCAG study found that 77 percent of residents — roughly 14.5 million people — “ride transit rarely or never.”   Only about 2 percent of the population in the SCAG region rides transit often, averaging 45 trips per month. While 20 percent of the residents ride occasionally, averaging 20 trips a month.    “If one out of every four of those people replaced a single driving trip with a transit trip once every two weeks, annual ridership would grow by 96 million — more than compensating for the losses of recent years,” reads the report. “The future of public transit in the SCAG region, then, will be shaped less by the mobility needs of people who do not own vehicles, and more by policy decisions that encourage vehicle-owning households to drive less and use transit more.”   The new information relating to increases in car ownership did not come as a huge surprise to Jager, who added that Metro is currently in the process of “reimagining and restructuring our bus system to better meet the needs of current and future riders.” And the agency is receiving feedback from residents related to any number of route and other service changes.   Adjustments to transit service and system operations are likely needed, said Ikhrata.   As an example, Ikhrata pointed to the more than 100 different operators of transit systems across the six county region, adding that ridership across these systems should be more seamless with one mobile ticketing app.   “That’s the kind of thing where you deploy technology and innovation to make sure that transit works,” he remarked.   For its part, Metrolink made changes to its mobile ticketing app to allow users to transfer to L.A. Metro Rail lines by scanning their phones at the rail gates thanks to new optic readers. Nearly a third of Metrolink riders are commuters transferring onto Metro Rail in Los Angeles.   Aside from technology, the time is also right to have some larger conversations about land-use and all forms of public policy around mobility, said Ikhrata. The most urban and transit-friendly areas in the six-county SCAG region make up less than 1 percent of the land area, home to 17 percent of the region's population, according to the study. However, these neighborhoods are also home to 45 percent of the transit commuters.    “This [study] is also telling us that if you want transit ridership to go up, you have to tackle land-use and development patterns,” he said. “Obviously, SCAG has no authority, or desire, to tell cities what to do, but cities need to pay attention to development patterns. And so therefore, the last question to ask is, how do we have a transportation system that works for us?”   If you want to change behavior — getting commuters to leave behind the car and take transit a few times a month — money can be a motivator.   “If you want those choice riders to take transit once in a while, you’re going to have to charge the right price for driving,” said Ikhrata.   “So if you can come to downtown Los Angeles and park for $5 or $10 a day, that’s not going to be an incentive for you to take transit,” he added. “But in cities like Manhattan where you pay $100 a day, you’ll think — maybe once in a while, you’ll take transit.”   Back at L.A. Metro, the bus system review — the first systemwide review since the 1990s — is set to be complete by April 2019. Officials say they plan to share the SCAG report with Metro’s own consultants, as they explore ideas related to getting car owners – both those new to ownership and longtime drivers — to choose transit.   “Metro believes it’s important to attract riders away from the automobile, if only to have them use the system once a week or once a month in our efforts to ease traffic congestion and improve the regions mobility,” Jager said.   With transit ridership dropping across the region — and many cities dealing with similar trends — even as hundreds of miles of service are added, it’s enough to have some wondering if it’s all worth the cost.   “Some reporter said, ‘Well, should we stop investing in transit?’” Ikhrata recalled. “That’s absolutely the wrong strategy. But we should be smart about how we invest in transit. We should use technology and innovation.   “We should take this as an opportunity say, ‘OK, ridership is declining. People are owning more vehicles. How can we make the transportation work for everybody,” he added. “That is really the question to ask.”