Congestion Drops in Several Key Freeway Corridors, But Regionwide Delay Reaches Highest Level Since 2000

OAKLAND, CA — Traffic delays along several of the Bay Area’s most congested freeway corridors declined last year, the Metropolitan Transportation Commission (MTC) and Caltrans reported today, though regionwide congestion — driven by several years of steady job growth and measured with greater precision in 2007 thanks to an expanded data-gathering effort — reached its highest level since 2000. While this year’s congestion numbers may drop under the weight of $4-a-gallon gasoline, rising carpool and transit use, a weak real estate market and other factors, the region experienced 161,700 vehicle hours of delay during the morning and afternoon commute periods on an average weekday during 2007 (see “Daily Freeway Delay by Bay Area County…”). This figure is second only to the 177,600 hours recorded in 2000, at the height of the dot.com boom.

Most notable among the list of congestion hot spots that experienced a reduction in delay in 2007 was the morning commute on westbound Interstate 80 from Hercules to the Bay Bridge. While this busy stretch once again topped the list of the region’s most congested freeway locations (see “Bay Area Freeway Locations with Most Delay…”), delay along the corridor fell nine percent in 2007 to 11,100 daily vehicle hours of delay from the 12,230 hours of delay recorded on an average day in 2006.

“The drop indicates improvements like the new FasTrak® configuration at the Bay Bridge toll plaza are having a beneficial impact on the notorious backups along that corridor,” said Caltrans Director Will Kempton. Other factors, such as rising FasTrak use, fuel prices that climbed from an average of $2.66 for a gallon of regular in January 2007 to $3.39 by December, and a rising number of workers commuting via transit and carpools during the year, also may have played a role in the reduction of morning congestion on this key freeway segment.

Reductions in delay also were recorded at several other gridlock-heavy Bay Area locations in 2007:

• The morning trip along westbound Interstate 580 across the Altamont Pass from Interstate 205 to Hacienda Drive fell one spot to number 4 on the Top 10 list for 2007, as average vehicle hours of delay dropped 4 percent to 5,120 last year (from 5,320 hours in 2006).
• The afternoon drive along northbound U.S. 101 and eastbound Interstate 80 in San Francisco, from the 101/Alemany Boulevard interchange to the Bay Bridge, retained its position as number 5 on the Bay Area’s Top 10 list, but vehicle hours of delay fell almost 3 percent to 4,760 from 4,880 in 2006. This was due in part to a traffic realignment in March 2007 as part of the ongoing reconstruction of the Bay Bridge West Approach.
• The afternoon commute on eastbound Route 4 from Bailey Road in Pittsburg to G Street in Antioch recorded a 17 percent decline in congestion in 2007 (3,140 vehicle hours of delay, down from 3,800 hours in 2006), dropping this segment to number 11 on the 2007 list from number 7 in 2006. A widening project that added an eastbound traffic lane along a portion of this segment in late 2006 helped to ease conditions in this corridor.

“The worst of the Bay Area’s congestion tends to be concentrated in a few familiar places,” observed MTC Vice Chair and Alameda County Supervisor Scott Haggerty, noting that eight of the top 10 regional hot spots were on the 2006 list as well — including Interstate 580 through the Altamont Pass and the Tri-Valley area. “But we’re starting to see results from the new strategies being used to unclog some of our most persistent bottlenecks. For example, afternoon traffic flow on eastbound 580 between Pleasanton and Livermore (number 2 on the Top 10 list for 2007) is already much better since ramp-metering was expanded this past January.”

The morning commute on westbound Interstate 580 through the Tri-Valley is expected to improve once metering lights are activated this fall — perhaps enabling a further reduction of delay in 2008, to build on the modest reduction witnessed in 2007.

“I’m one of thousands of drivers,” continued Haggerty, “who expect an even bigger payoff from new carpool lanes that will be added to I-580 in the Tri-Valley area in the next few years.” Construction on the eastbound carpool lane, funded through the $19.9 billion Proposition 1B infrastructure bond approved by voters in 2006, is scheduled to begin this summer.

The only newcomers to the annual Top 10 list are the southbound morning commute along Interstate 880 from Marina Boulevard in San Leandro to the Route 92 interchange in Hayward, which climbed all the way to number 8 on the list from number 26 last year; and the afternoon trip on southbound U.S. 101 from Great America Parkway in Santa Clara to North 13th Street/Oakland Road in San Jose, which rose to the number 10 position from number 14 in 2006.

Different Picture Regionwide

At the regional level, the rise in reported commute-hour congestion for 2007 is due in large part to MTC and Caltrans mounting a more robust data collection effort last year than in recent years. “We beefed up our congestion monitoring effort to collect and analyze data from about 90 separate, typically less-congested freeway segments that had not been monitored since 2003,” explained Caltrans District 4 Director and MTC Commissioner Bijan Sartipi. “In so doing, we recorded congestion in one year that likely had been building up over several years.” The likeliest explanation for the increase in congestion throughout the region in recent years is the growth of the Bay Area economy. In 2007, some 53,000 jobs were added to payrolls in the nine-county region (source: California Employment Development Department). This marked the third consecutive year of regional employment growth, following increases of about 61,000 jobs in 2006 and 26,000 jobs in 2005. Congestion on Bay Area freeways has grown steadily over this period, rising 33 percent since 2003, the last year prior to 2007 when a complete survey (comprising some 160 freeway segments) of commute-hour traffic conditions was taken.¹ The close historical correlation between the performance of the Bay Area’s economy (as represented by number of jobs) and the amount of commute-hour congestion on the region’s freeways is illustrated in the chart “Vehicle Hours of Delay vs. Employment, San Francisco Bay Area, 1998-2007”.

Alameda County Suffers Biggest Share of Backups

At the county level, Alameda County experienced the greatest amount of freeway congestion (defined as average speeds below 35 miles per hour for 15 minutes or longer), with 63,900 daily vehicle hours of delay. Coming in a distant second, with 28,300 daily vehicle hours of delay, is Santa Clara County, and Contra Costa County a close third at 26,600 hours. Marin County, San Francisco and San Mateo County are next in line with, respectively, 11,200, 10,600 and 10,500 daily vehicle hours of delay.

MTC is the transportation planning, financing and coordinating agency for the nine-county San Francisco Bay Area. Caltrans is responsible for the planning, design, construction, maintenance and operation of the state highway system.

In previously released congestion tallies for the years 2004 through 2006, MTC and Caltrans carried forward the 2003 readings for approximately 90 less-congested freeway segments that were monitored anew in 2007.

Contact:

John Goodwin, MTC: (415) 778-5262

Lauren Wonder, Caltrans: (510) 286-6120