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Rideshare firms have snarled up traffic in San Francisco: study


ONE of the early promises of the ride-hailing era ushered in by Uber and Lyft was that the new entrants would complement public transit, reduce car ownership and help alleviate congestion.

But a new study on San Francisco has found the opposite may be in fact be true: far from reducing traffic, the companies increased delays by 40 per cent as commuters ditched buses or walking for mobile-app summoned rides.

Published on Wednesday in Science Advances, the study went back to 2010, before the advent of so-called transportation network companies (TNCs), and compared journey times and road conditions with 2016, the year they became a common sighting.

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San Francisco, where Lyft and Uber are headquartered, grew from 805,000 inhabitants to 876,000 during that period, as 150,000 jobs were added and the road network updated.

The authors, from the University of Kentucky and the San Francisco County Transportation Authority (SFCTA), accounted for these changes via a computer model that asked: what would things look like if ride-hailing companies had not come on the scene?

Greg Erhardt, an assistant professor of engineering at the university, told AFP his team had found "some substitution" from private cars to TNCs as well as a slight increase in carpooling. "But the net effect is that two-thirds of TNCs are new cars added to the roadway, that would otherwise not be present," he said.

They also found that weekday vehicle hours of delay - defined as the difference in travel time in congested versus free-flow conditions - increased by 62 per cent between 2010 and 2016. By contrast, in the simulated model without ride-hailing companies, delays went up by only 22 per cent - meaning that the TNCs were responsible for 40 per cent of the increase.

The findings were challenged by Lyft, which said the study had failed to account for increased freight and commercial deliveries - an area in which Amazon and others have aggressively expanded in recent years, as well as tourism growth.

"Lyft is actively working with cities on solutions backed by years of economic and engineering research, such as comprehensive congestion pricing and proven infrastructure investment," the company said in a statement noting its investments in shared rides and bikes.

Uber called for more widespread congestion charging, arguing that "while studies disagree on causes for congestion, almost everyone agrees on the solution". The study comes as rideshare drivers in major US cities were set to stage a series of strikes ahead of Uber's keenly anticipated Wall Street debut. Lyft went public in March.

Proponents of ridesharing often use the argument that the majority of journeys take place at non-peak times, such as when people have gone for a night out and are returning home from bars.

But the study found peaks occurring at 7 am and 8 am and then again around 5 pm and 6 pm.

Among the cars' most disruptive activities on traffic flow were curbside pickups and drop-offs, especially on major arterial roads, it found.

Another notable effect was so-called "deadheading", which Prof Erhardt explained as driving around in search of the next customer. "It doesn't serve a purpose in terms of transporting a person. So that's purely an addition to traffic." AFP