The San Francisco County Transportation Authority’s 2018 TNC and Congestion report analyzed how TNC’s affected roadway congestion in San Francisco.
San Francisco County Transportation Authority’s 2018 TNCs and Congestion report provides the first comprehensive analysis of how Transportation Network Companies (TNC) collectively have affected roadway congestion in San Francisco.
The study sought to identify the extent to which TNCs contributed to increased roadway congestion in San Francisco between 2010 and 2016, relative to other potential contributing factors including employment growth, population growth, and changes to the transportation system.
The study utilized a unique TNC trip dataset provided to the Transportation Authority by researchers from Northeastern University in late 2016, as well as INRIX data, a commercial dataset which combines several real-time GPS monitoring sources with data from highway performance monitoring systems.
The Final Report:
- Identifies common measures of roadway congestion;
- Discusses factors that contribute to roadway to congestion; and
- Quantifies the relative contributions of different factors, including population, employment, road network changes and TNCs, to observed changes in congestion in San Francisco between 2010 and 2016, by location and time of day.
The final report found that Transportation Network Companies (TNCs) accounted for approximately 50 percent of the rise in congestion in San Francisco between 2010 and 2016, as indicated by three congestion measures: vehicle hours of delay, vehicle miles travelled, and average speeds.
Employment and population growth were primarily responsible for the remainder of the worsening congestion.
Major findings of the TNCs & Congestion report show that collectively the ride-hail services accounted for:
Consistent with prior findings from the Transportation Authority’s 2017 TNCs Today report, TNCs also caused the greatest increases in congestion in the densest parts of the city—up to 73 percent in the downtown financial district - and along many of the city’s busiest corridors. TNCs had little impact on congestion in the western and southern San Francisco neighborhoods.
The report also found that changes to street configuration (such as when a traffic lane is converted to a bus-only lane), contributed less than 5 percent to congestion.