Skip to main content

California State Route 172 (former California State Route 36 over Mineral Summit.

In May 2017 upon leaving Lassen Volcanic Park I took a detour from Morgan Summit to California State Route 172.  California State Route 172 is one of the last remaining segments of one lane State Highway in California and was a former alignment of California State Route 36.


California State Route 172 ("CA 172") is a 9 mile loop from CA 36 from Mineral east to the vicinity of Mill Creek in rural Tehama County.  Much of CA 172 as noted above is a one-lane state highway over Mineral Summit and was once the original alignment of CA 36. 


 

Part 1; the history of California State Route 172

The history of CA 172 is tied directly to the earliest alignment of CA 36.  The origins of CA 36 date back to the era of the California Gold Rush.  Specifically what is now CA 36 between Red Bluff east to Susanville was constructed during the 1860s as a part of two wagon routes according to the September 1950 California Highways & Public Works article titled "Crossing the Sierra."   In particular the Humboldt Road was the wagon road that blazed a path over Fredoyner Pass.  



In chronological order the first segment of State Highway that would be adopted as part of Future CA 36 was a route between the communities of Kuntz (now Mad River) and Peanut (approximately) by way of 1907 Legislative Chapter 117.  In time this segment of highway between Kuntz and Peanut would come to be known as Legislative Route 35 ("LRN 35").  The original Legislative language of the Kuntz-Peanut State Highway was as follows:

"Locating, surveying, and constructing a state highway connecting the present county road systems of any one or all of the counties of Trinity, Tehama, and Shasta with the road system of Humboldt County."

No known State Highway Maps from 1907 have been published online, further the above description is vague beyond that it was clear that described "present county roads."  For graphic fidelity purposes this is approximately what the Peanut-Red Bluff Highway would have looked like.  


The 1909 First State Highway Bond Act was approved by voters in 1910.  The 1909 First State Highway Bond Act added several additional pieces of highway to the State Inventory which would be come part of future CA 36:
 
1.  LRN 3 was plotted between the Oregon State Line south to Sacramento.  A very small portion of LRN 3 would carry CA 36 on a multiplex with future US Route 99.  
2.  LRN 29 east from Red Bluff to Susanville by way of Mineral Summit. 

The 1918 Division of Highways State Map reveals LRN 29 as a proposed highway from Red Bluff east to Coppervale and under construction east to Susanville. 

LRN 35 is shown as a special appropriations road between Mad River and Peanut. 

The 1919 Third State Highway Bond Act extended LRN 29 east to the Nevada State Line.  Future CA 36 would utilize LRN 29 from Susanville to future CA 7/US 395.  The extension of LRN 29 first appears on the 1920 Division of Highways State Map.  

In 1933 LRN 35 west extended west from Mad River to LRN 1/US 101 in Alton along with LRN 29 being was extended west from Red Bluff LRN 35.  Thusly, all the highways that would become the initial CA 36 were finally brought into State Inventory.  These changes to LRN 29 and LRN 35 can be seen on the 1934 Division of Highways State Map


Notably LRN 86 from Lassen Volcanic National Park-Mineral Road to Mineral along with LRN 83 (which ended at LRN 29) to Morgan were also added to the State Highway System.  These Legislative Routes would later hold significance when CA 36 was realigned over Morgan Summit. 

The Sign State Routes were announced in the August 1934 California Highways & Public Works.  CA 36 was announced as a Sign Route originating from US 101 near Scotia to Route 7 near Susanville by way of Red Bluff.  


CA 36 can be seen for detail for the first time on the 1935 Gousha Highway Map of California.  Note; CA 36 is shown traversing LRN 29 by way of what is presently CA 172 over Mineral Summit.  

It is unclear when CA 36 moved off of LRN 29 over Mineral Summit.  One of the few maps I can find showing in fully clear detail CA 36 over LRN 29 via Mineral Summit is the 1935 USGS Map of Payne's Creek.  USGS Maps from the 1950s show CA 36 realigned via LRN 86 and LRN 83 over Morgan Summit. 

A May 1935 Division of Highways Map shows the progress of signing the US Routes and Sign State Routes in California.  CA 36 is shown to have been fully signed over Mineral Summit via LRN 29.  



 
 
There seems to be some evidence that CA 36 may have been realigned over Morgan Summit by 1940.  The 1940 Division of Highways State Map shows LRN 86/LRN 83 paved over Morgan Summit whereas Mineral Summit on LRN 29 is still shown to be a Oiled Earth or Gravel surface.  It is likely that the more favorable grades of LRN 86/LRN 83 made for a far more attractive through route for CA 36 to be signed over.  
 

During the 1964 State Highway Renumbering what had been CA 36/LRN 29 over Mineral Summit was reassigned as CA 172.  The definition of CA 172 in 1964 was "from Route 36 at Mineral to Route 36 near Morgan."  The newly created CA 172 can be seen on the 1964 Division of Highways State Map.  


The only change to CA 172 since 1964 was the eastern terminus to "near Morgan Summit" as part of 1984 Legislative Chapter 409.


Part 2; a drive on California State Route 172

CA 36 east enters Mineral and intersects it's original alignment at CA 172 at Postmile TEH 81.13.  Post Office service in Mineral was established in 1894.  The community takes it's name from a nearby Mineral Spring.  Mineral is located at 4,918 feet above sea level.

From Mineral CA 172 eastbound begins as a one-lane highway.


CA 172 eastbound travels through a small valley before ascending onto a mountain grade.  CA 172 more or less straddles the divide between where the Sierra Nevada Mountains transitions into the volcanic Cascade Mountains.


I didn't encounter another vehicle on CA 172, most of the one-lane portion of the highway closes during winter months.  The climb to Mineral Summit is fairly straight-forward although a little rougher than the typical one-lane state highways I've encountered in the past.  Mineral Summit is located at Post Mile TEH 2.274.



The descent to Mill Creek on CA 172 east from Mineral Summit is fairly tame given there isn't much of an elevation drop.  CA 172 eastbound enters Mill Creek at approximately Postmile TEH 5.78.  Mill Creek is located at 4,737 feet above sea level.  Mill Creek takes it's name from the nearby creek which CA 172 follows east of Mineral Summit. 





East of Mill Creek CA 172 widens out to the width of a two lane highway but lacks a center stripe.  Winter plowing of CA 172 occurs from Mill Creek east to to CA 36/CA 89.  CA 172 eastbound terminates CA 36/CA 89 at Postmile TEH 8.91.



The CA 172 junction from CA 36 west/CA 89 north.


Comments

Popular posts from this blog

California State Route 232

This past month I drove the entirety of California State Route 232 in Ventura County. CA 232 is an approximately 4 miles State Highway aligned on Vineland Avenye which begins near Saticoy at CA 118 and traverses southwest to US Route 101 in Oxnard.  The alignment of CA 232 was first adopted into the State Highway System in 1933 as Legislative Route Number 154 according to CAhighways.org. CAhighways.org on LRN 154 As originally defined LRN 154 was aligned from LRN 9 (future CA 118) southwest to LRN 2/US 101 in El Rio.  This configuration of LRN 154 between CA 118/LRN 9 and US 101/LRN 2 can be seen on the 1935 California Division of Highways Map of Ventura County. 1935 Ventura County Highway Map According to CAhighways.org the route of LRN 154 was extended west from US 101/LRN 2 to US 101A/LRN 60 in 1951.  Unfortunately State Highway Maps do not show this extension due to it being extremely small. During the 1964 State Highway Renumbering LRN 154 was assigned CA 232.  Of n

Interstate 40 and the H-Bomb

Interstate 40 within California is entirely contained to San Bernandio County over a course of 155 miles from Interstate 15 in Barstow east to the Arizona State Line at the Colorado River.  Interstate 40 is aligned entirely in the Mojave Desert over the same general corridor established by US Route 66 and the National Old Trails Road.   Interstate 40 is known as the Needles Freeway and has an interesting backstory which included the prospect of the Bristol Mountains being excavated by way of nuclear blasts as part of Operation Carryall.   Part 1; the history of Interstate 40 in California The focus on this blog will be primarily centered around the construction of Interstate 40 ("I-40") within California.  That being said the corridor of automotive travel east of Barstow to the Arizona State Line was largely pioneered by the National Old Trails Road ("NOTR")   In April of 1912 the NOTR was organized with the goal of signing a trans-continental highway between Baltim

Interstate 15 Exit 239 to Zzyzx Road; intersecting the Mojave Road and Tonopah & Tidewater Railroad

    Interstate 15 Exit 239 in the Mojave Desert of northern San Bernardino County, California accesses the well known oddity of Zzyzx Road.  Zzyzx Road connects 4.5 miles from Interstate 15 to a small community of the same name which is located on the shore of the dry Soda Lake.  "Zzyzx" was coined in 1944 by Curtis Howe Springer as what he promoted as to be last word in the English Language.  On the surface Zzyzx appears to be something of a modern invention but the area has significant overall historical importance as part of a transportation corridor through the Mojave Desert.  Zzyzx lies at a point which was the intersection of the Mojave Road of the 19th Century the Tonopah & Tidewater Railroad of the early 20th Century.   The backstory of Soda Springs, the Mojave Road, Tonopah & Tidewater Railroad and Zzyzx The present site of Zzyzx is located upon a natural spring along the western shore of Soda Dry Lake.  This spring has historically been known as "Soda S