Former US Route 466 Rocky Canyon

Max Rockatansky · May 13, 2021, 10:49:22 PM

I know that I hit on this in one of my US Route 466 blogs on Gribblenation but I figured that I would give this a look in the AASHO Database. From what I posted on the Gribblenation Facebook page:

One of the biggest mysteries of the US Route System within California was the original alignment of US Route 466 west from Shandon to Atascadero via Creston on Legislative Route Number 125. Specifically Legislative Route Number 125 west of Creston traversed Rocky Canyon via a dirt alignment on Rocky Canyon Road towards the Salinas River over to what is now Acacia Road in Atascadero. The AASHTO Renumbering Database reveals while this segment of US Route 466 was indeed defined as traversing Rocky Canyon it was never signed by the Division of Highways. The Division of Highways made improvements to California State Route 41/Legislative Route Number 33 by early 1958 and sought AASHO approval to relocate US Route 466 on a multiplex between Shandon and Paso Robles. The AASHO granted the request of the Division of Highways to relocate US Route 466 during late June of 1958.

Legislative Route Number 125 west of Creston was relocated to a new grade west of Creston during 1962. Rocky Canyon Road was eventually abandoned and began to erode. Today much of Rocky Canyon Road and former US Route 466 is part of the Rocky Canyon Trail which can be reached via Atascadero.

https://www.facebook.com/72868503020/posts/10157966895623021/?d=n

Max Rockatansky · May 21, 2021, 08:14:06 PM

From 1933 through 1958 US Route 466 was aligned from downtown Atascadero eastward through Rocky Canyon towards Creston and Shandon. This initial alignment of US Route 466 was apparently never signed given it included a dirt segment through Rocky Canyon which had been added into the State Highway System in 1933 as part of Legislative Route Number 125. US Route 466 in 1958 was shifted west of Shandon to Atascadero via a multiplex of California State Route 41 west to Paso Robles and southbound US Route 101. This alignment swap of US Route 466 was requested by the California Division of Highways to the AASHO upon the completion of an upgrade to California State Route 41 (Legislative Route Number 33) between Shandon-Paso Robles. In 1962 Legislative Route Number 125 through Rocky Canyon would go through a maintenance swap between the Division of Highways and San Luis Obispo County given it was more suited to overall State Transportation needs.

In time former US Route 466 through Rocky Canyon was abandoned and eroded away. Much of the former right of way of US Route 466 in Rocky Canyon is now occupied by the CalPortland Rocky Canyon Quarry and Rocky Canyon Trail. Given US Route 466 in Rocky Canyon is one of the last major segments of the US Route System in California not to receive much coverage from historic highway groups I figured it was time to change that.

Below is a photo summary of the original alignment of US Route 466 as it was from downtown Atascadero west through Rocky Canyon:

IMG_1678 by Max Rockatansky, on Flickr

Photo 2: Former US 466/West Mall facing eastbound is within sight of the 1918 Atascadero Administration Building.

IMG_1683 by Max Rockatansky, on Flickr

Photo 3: East of downtown Atascadero US 466 on West Mall would have crossed Atascadero Creek via a concrete arch bridge which was built in 1921.

IMG_1704 by Max Rockatansky, on Flickr

Photo 4: The 1921 Atascadero Creek Bridge still bears Postmile markings due to it being part of post 1964 CA 41 into the 1990s.

IMG_1713 by Max Rockatansky, on Flickr

Photo 5: Former US 466 eastbound would have made a soft transition onto Capistrano Avenue upon crossing Atascadero Creek.

IMG_1705 by Max Rockatansky, on Flickr

Photo 6: Former US 466 eastbound followed Capistrano Avenue to the 1902 Southern Pacific Railroad underpass.

IMG_1730 by Max Rockatansky, on Flickr

Photo 7: The 1902 Southern Pacific Railroad Underpass as seen in the September 1950 California Highways & Public Works.

F by Max Rockatansky, on Flickr

Photo 8: Upon crossing under the Southern Pacific Railroad former US 466 eastbound would have made a hard right onto Sycamore Road.

IMG_1732 by Max Rockatansky, on Flickr

Photo 9: Former US 466/Sycamore Road crosses under modern CA 41.

IMG_1737 by Max Rockatansky, on Flickr

Photo 10: Former US 466 followed Sycamore southeast along the Salinas River and made a left hand turn at Acacia Road.

IMG_1745 by Max Rockatansky, on Flickr

Photo 11: Former US 466 eastbound would have crossed the Salinas River via a pony truss bridge which was destroyed in 1995. This structure was also part of post-1964 CA 41 which led to the highway being realigned. Upon crossing the Salinas River US 466 eastbound would have turned right on Rocky Canyon Road, post 1964 CA 41 would have turned left.

IMG_1747 by Max Rockatansky, on Flickr

Photo 12: US 466 would have followed Rocky Canyon Road all the way eastward through Rocky Canyon to what is now CA 229 near Creston. Rocky Canyon Road is closed to the public beyond the intersection with Halcon Road. The intersection of Rocky Canyon Road and Halcon Road serves as the Rocky Canyon Trailhead.

IMG_1795 by Max Rockatansky, on Flickr

Photo 13: Although general motorized traffic cannot drive through former US 466 through Rocky Canyon it is available to hikers.

IMG_1798 by Max Rockatansky, on Flickr

Photo 14: Former US 466 enters the CalPortland quarry where the pavement ends. Hikers are directed to walk on a trail built alongside the former right of way of US 466 for about a half mile.

IMG_1813 by Max Rockatansky, on Flickr

Photos 15-16: Upon passing through the CalPortland Quarry plant the Rocky Canyon Trail briefly rejoins the maintained part of former US 466 before splitting eastward towards the abandoned segment.

IMG_1834 by Max Rockatansky, on Flickr

IMG_1838 by Max Rockatansky, on Flickr

Photos 17-24: Former US 466 within upper Rocky Canyon is heavily weather but there is some evidence of it being a roadway in the form of ruined highway embankments. Former US 466 climbs eastward to the top of Rocky Canyon towards Creston.

IMG_1839 by Max Rockatansky, on Flickr

IMG_1854 by Max Rockatansky, on Flickr

IMG_1866 by Max Rockatansky, on Flickr

IMG_1869 by Max Rockatansky, on Flickr

IMG_1880 by Max Rockatansky, on Flickr

IMG_1884 by Max Rockatansky, on Flickr

IMG_1892 by Max Rockatansky, on Flickr

IMG_1895 by Max Rockatansky, on Flickr

Photo 25: Upon emerging from Rocky Canyon former US 466 on abandoned Rocky Canyon Road has some remaining macadam surfacing which can be found.

IMG_1904 by Max Rockatansky, on Flickr

Photo 26: A look westward near the top of Rocky Canyon over former US 466.

0 by Max Rockatansky, on Flickr

Photo 27: A look west on maintained segment of Rocky Canyon Road from CA 229 reveals how former US 466 would have once appeared.

IMG_2070 by Max Rockatansky, on Flickr

Photo 28: A look east as where former US 466 would have transitioned from Rocky Canyon Road onto pavement near Creston.

IMG_2071 by Max Rockatansky, on Flickr

Photos 29-34: A look at the documentation in the AASHO Database showing the request by the Division of Highways to relocate US 466 out of Rocky Canyon northward to a multiplex of CA 41.

A by Max Rockatansky, on Flickr

B by Max Rockatansky, on Flickr

C by Max Rockatansky, on Flickr

D by Max Rockatansky, on Flickr

E by Max Rockatansky, on Flickr

Max Rockatansky · May 21, 2021, 09:31:50 PM

I forgot to post the full album link in the proceeding post:

https://flic.kr/s/aHsmVKpNny

I tried my best to replicate how the 1902 Southern Pacific Underpass looks today versus 1950:

F by Max Rockatansky, on Flickr

IMG_1752 by Max Rockatansky, on Flickr

We do have an existing blog on this topic on Gribblenation but suffice to say it needs an updated. I cobbled said blog in with the entirety of CA 229, it might be time to split that off onto it's own entry.