Skip to main content

California State Route 109

On the south side of San Francisco Bay between US Route 101 and California State Route 84 there are to unsigned short surface routes; CA 109 and CA 114.  Both CA 109 and CA 114 are located with the boundaries of Menlo Park and East Palo Alto, this entry is about the former route CA 109.


CA 109 is a 2 mile state highway running on University Avenue between US 101 in East Palo Alto to CA 84 in Menlo Park.  Northbound traffic departing US 101 from exit 403 must join Donohoe Street and take a brief western jog to reach CA 109 on University Avenue.



CA 109 north travels through East Palo Alto and enters Menlo Park at Notre Dame Avenue.  Notre Dame Avenue north to CA 84 was the first segment of CA 109 that was adopted by Caltrans.  Traffic is slow with speed limits as low as 25 MPH in East Palo Alto.






CA 109 on University Avenue crosses a set of rails before terminating at CA 84.




The north terminus of CA 109 is within view of modern Dumbarton Bridge crossing San Francisco Bay.  The Dumbarton Bridge is a Twin Concrete Girder design which is 1.63 miles in length.  The modern Dumbarton Bridge was opened to traffic in 1984 and was a replacement for the 1927 span which was the first highway crossing of San Francisco Bay.


According to CAhighways the current routing of CA 109 was created in 1984 from CA 84 south on University Avenue to Notre Dame Avenue.  In 1988 legislation was passed which allowed CA 109 to be extended south on University Avenue to US 101 but maintenance wasn't picked up apparently until 1997.

CAhighways on CA 109

The first CA 109 was along Sunset Cliffs Boulevard in San Diego.  The first CA 109 first appears on the State Highway Map in 1964 and was apparently created out of legislation in 1963 according to CAhighways.org.  The original CA 109 was deleted in 1972 and became an extension of I-8. 

1964 State Highway Map 

Interestingly the second CA 109 appears on the 1986 State Highway Map City Insert as CA 209 running south from CA 84 to Notre Dame Avenue.

1986 State Highway Map City Insert

On the 1988 State Highway Map City Insert CA 109 is shown correctly, I'm not sure if the 1986 map was an error.

1988 State Highway Map City Insert

CA 109 appears as a complete route between CA 84 and US 101 on the 1990 State Highway Map City Insert.

1990 State Highway City Insert

Comments

Popular posts from this blog

Cajon Pass; Cajon Pass Toll Road, National Old Trails Road, US Route 66/91/395 and Interstate 15

This past weekend I spent some time in Cajon Pass traversing the many historic road alignments. Cajon Pass is located in San Bernardino County, California along the San Andreas Fault.  Cajon Pass  serves the boundary line between the Mojave Desert, the San Gabriel Mountains, San Bernardino Mountains and San Bernardino Valley.  Cajon Pass is historically one of the most traveled transportation corridors in American California and presently is served by four rail lines, Interstate 15 and California State Route 138. While Cajon Pass is known mostly for carrying US Route 66 it has carried numerous other signed highways that have had a significant impact on regional and national road travel.  While this is my best attempt to compile everything from the best sources I could find into one single transportation history blog regarding road travel in Cajon Pass I suspect as time goes on this article will be frequently updated.  If you have any information that you ...

Pardee Dam Road

Pardee Dam is a 358-foot-high concrete structure located near Campo Seco at the Calaveras County and Amador County Line.  Pardee Dam impounds the Mokelumne River which forms the namesake Pardee Reservoir.  Pardee Dam was completed during 1929 and is part of the East Bay Municipal Utility District.  Pardee Dam is accessed by the namesake Pardee Dam Road which crosses the structure via the one-lane road seen as the blog cover photo.   Part 1; the history of Pardee Dam Road The closest community to Pardee Dam is that of Campo Seco on the Calaveras County side of the Mokelumne River.  Campo Seco was founded in 1850 by Mexican Miners who worked placer claims in Oregon Gulch during the height of the California Gold Rush.  Campo Seco would reach a population of about three hundred by 1860 spurred by the numerous mining claims in the area.  Main Street of Campo Seco flowed directly into the Campo Seco Turnpike which had been authorized by the California L...

Grand Loop Road of Yellowstone National Park

  Grand Loop Road is a 140 mile loop highway which traverses the interior of Yellowstone National Park.  Grand Loop Road connects all of the major attractions and geological features of Yellowstone National Park along with the entrance roads.  Grand Loop Road is a seasonal highway and despite some conjecture never has been part of the US Route System.   Part 1; the history of Grand Loop Road The majority of history pertaining to Grand Loop Road was taken from the below National Park Service article: Historic Roads - Yellowstone National Park (U.S. National Park Service) (nps.gov) Yellowstone was declared the first National Park of the United States on March 1st, 1872.  The first real highway to access Yellowstone National Park came in 1873 when a tolled facility was constructed from Bozeman, Montana via Yankee Jim Canyon to Mammoth Hot Springs.  Numerous attempts were made to fund construction of roadway infrastructure during the early years of Yellows...