Date:
Tuesday, September 01, 2009
Contact:
Lloyd Brown, WSDOT Communications, 360-705-7076
OLYMPIA – The recently published 2009 National Scorecard Mid-Year Update by INRIX Corporation finds that congestion and travel times nationally have “bottomed out” in the first half of 2009. Based on gas prices and economic trends, INRIX predicts that congestion is at the lowest possible levels and increasing. However, the report finds that peak period congestion levels in the Seattle, Tacoma, and Bellevue areas have further decreased (by 8 percent) compared to the first half of 2008.
INRIX’s findings that congestion is decreasing for the Seattle, Tacoma, and Bellevue are consistent with WSDOT’s congestion report on Puget Sound travel times published in its most recent quarterly report, the June 30, 2009 Gray Notebook.
“The gas tax investments made in 2003 and 2005 to eliminate chokepoints and bottlenecks in the transportation system are starting to pay off,” said Paula Hammond, Washington Transportation Secretary. “There is no single solution for traffic congestion, but experience has shown that we can reduce congestion by focusing on three key strategies: adding road capacity strategically, operating the system we have efficiently, and providing choices that help manage demand. We call that Moving Washington. The Inrix data supports our own findings – our Moving Washington approach is having a positive effect on congestion.”
High fuel prices and the economic recession have contributed to the improvement in travel times, as well as WSDOT’s congestion relief projects. For example, the Tukwila to Bellevue trip showed sustained year-over-year average travel time savings of 12 minutes during the morning commute. Data suggest that a contributing factor to this improvement was the completion of an auxiliary lane near the I-90 interchange that opened in January 2009. The trip time improvement has been largely sustained for the nearly six months following that lane opening.
INRIX reports that the worst bottleneck in the central Puget Sound is SR 16 eastbound at Union Avenue in Tacoma, and cites the construction of the Nalley Valley Viaduct Project as a contributing factor. Despite the slowdown due to construction at this location, volumes did not decrease and the impact of the bottleneck had a minor impact on total commute times for those travelling the full length of this commute corridor. This project is one of many mobility improvement projects under construction that, once completed, will help improve travel times and reduce congestion along some of the regions most congested corridors.
WSDOT is currently delivering the largest capital construction program in Washington’s history, including hundreds of safety and congestion relief projects funded by the 2003 and 2005 gas tax, worth $13.4 billion. As of June 30, WSDOT has completed 194 of 391 projects, and by September 30, 2009, 284 of the 391 projects (73 percent) will either be completed or under construction.
Congestion relief projects account for 116 of the 391 total projects. In addition, the state is leveraging $492 million, in American Recovery and Reinvestment Act funds to deliver $1.4 billion in projects.
Comparing the Inrix and WSDOT reports
INRIX examined a limited number of metrics based on free flow speeds for its analysis. The use of free flow speeds may overstate levels of congestion. WSDOT’s congestion performance reporting examines system performance using numerous metrics based on maximum “throughput” speeds when the system is operating at its greatest efficiency. In addition, WSDOT evaluates the impacts of transit and operational strategies such as incident response in reducing congestion, and examines trends for highway safety related to changes in travel demand.
WSDOT’s congestion report found that during the first half of 2009 commute times during peak periods improved in the central Puget Sound region on 13 of 18 major commute routes in the Seattle area compared to the first half of 2008.
For example:
- The morning commutes from Federal Way to Seattle via I-5 and Tukwila to Bellevue via I-405 saw the biggest improvements, with travel times dropping by 7 minutes and 12 minutes respectively.
- Peak period volumes were mixed during the first six months of 2009, with half of the 18 locations showing a drop in peak period volumes, and the other half showing higher volumes, compared to the first half of 2008. INRIX does not report volume data.
- The improvements in travel times can be attributed to the economic recession and key congestion relief projects and strategies on several high-demand commute routes.
- Over a two-year period (first half of 2009 versus the first half of 2007), all 18 commutes analyzed showed an overall drop in travel times, with 12 of the 18 commutes faster by between 2 and 12 minutes.
View WSDOT’s congestion report (pdf) published last week.
As noted in the INRIX report, WSDOT also found that most routes experienced larger drops when comparing the first half of 2007 to 2008 than from comparing the first half of 2008 to 2009. This may indicate the decrease in congestion is slowing down. Only a few routes experienced slight increases. However, whether congestion has “bottomed out” yet or not in Washington State remains to be seen. Within King County, unemployment was still rising as June 2009 came to a close, and WSDOT continues to deliver congestion relief projects throughout the region.
WSDOT publishes its comprehensive Annual Congestion Report each fall looking at system performance statewide and in the Seattle urban area. Read the 2008 Annual Congestion Report (pdf). WSDOT also publishes semi-annual travel time trend reports that look at changes in travel times and other trends on major commute routes in the central Puget Sound.
Recent congestion reports:
WSDOT keeps people, businesses and the economy moving by operating and improving the state's transportation systems. To learn more about what we're doing, go to www.wsdot.wa.gov/news for pictures, videos, news and blogs. Real time traffic information is available at www.wsdot.wa.gov/traffic or by dialing 5-1-1.
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