Category Archives: Southern California

Image of the Week – 7/17/2016

Four Level Interchange in 1998. US 101 goes left/right and SR-110 goes up/down.
Four Level Interchange in 1998. US 101 goes left/right and SR-110 goes up/down.

New Site Feature – Online Forum

I’m trying out a new idea for SocalRegion – a web forum. I’m not quite sure where this will go or how well it will be used, but there is no better way than to implement it. I plan to add subsections that mirror each section of the website in the future. Right now, I just have geology and roads. This is “Southern California Regional Rocks and Roads” after all. Right now, access to the forum is through the menu on the left side of the site. Please tell us what you think about the new addition!

Image of the Week – 7/7/2016

Southwestern Downtown Los Angeles from the US Bank Tower - SkySpace-LA. The building under construction in the Wilshire Grand Tower, soon to be taller, but not actually higher than the US Bank Tower.
Southwestern Downtown Los Angeles from the US Bank Tower – SkySpace-LA. The building under construction in the Wilshire Grand Tower, soon to be taller, but not actually higher than the US Bank Tower.

Old Highway 78 near Oceanside, CA

State Route 78, one of the original State Highways in the region, has has undergone many changes since it was originally built. Most of the original routing west of Vista, CA, known as Vista Way, has been eliminated by the current alignment of the highway. By the 1960’s, State 78 was an expressway west of Vista, CA. It was gradually upgraded further to a full freeway, bypassing or replacing yet more of the original alignment. Today, there are some original sections still around, albeit very short. The two main sections of old paving, mostly dating to the late 1920’s to early 1930’s, exists near El Camino Real and College Ave in the Oceanside area.

The first section, near El Camino Real, is located on Haymar Dr / S Vista Way and is only partly exposed. Here, the concrete has been repaved but is showing through some of the potholes.

S Vista Way just west of El Camino Real in Oceanside. Note the concrete peeking out from under the asphalt.
S Vista Way just west of El Camino Real in Oceanside. Note the concrete peeking out from under the asphalt.
Closer view of the concrete paving beneath.
Closer view of the concrete paving beneath.

To the east of this section, there is another and more exposed bit of old paving. Adjacent to the Marron Adobe on Haymar Dr (old Vista Way), this paving still retains the feel of the old roadway. No date stamps could be found, but the style of the concrete seems to date it from 1926 to 1935.

Intact section of concrete adjacent to the Marron Adobe.
Intact section of concrete adjacent to the Marron Adobe.
Marker for the Marron Adobe, as in Marron Road "fame".
Marker for the Marron Adobe, as in Marron Road “fame”.

Other sections of older alignments do still exist, but they are all completely reconstructed and no longer retain the old paving.

Motorcycling Pages?

I enjoy riding my motorcycle throughout Southern California. In my exploration of the region by motorcycle, I’ve found many roads that are a lot of fun to ride. As such, I have been thinking about adding some pages about motorcycling in the region. What the focus of the pages may be and what sort of extent they may cover is still undecided. Topics such as riding tips specific to Southern California, recommended roads, and other items of interest may be included. I am looking to see if there is indeed interest in adding these pages. If you are interested, please send me feedback and / or vote in the poll, which is on the left sidebar.

Image of the Week – 1/31/2016

The Arroyo Seco Parkway near Orange Grove Ave in South Pasadena, CA.
The Arroyo Seco Parkway near Orange Grove Ave in South Pasadena, CA.

Help the USGS with Earthquakes!

How can you help the United States Geological Survey? One simple way is to report to them when you feel an earthquake. This data helps them determine magnitude of the earthquake, how the geology affects that, and how the type of structure reacts to the event. Most earthquakes larger than 4.0 are listed in the “Events”  section of the page. So, help the USGS understand how earthquakes affect our region by contacting them at: “Did You Feel It?

Landslide Threats in Southern California

Southern California has many areas that are susceptible to landslides in many forms. The past couple of weeks have demonstrated that these slides can have dramatic affects on the regions infrastructure. While most slides aren’t that preventable, the damage they can create can be mitigated.

Understanding the signs of a pending landslide are fairly easy and should not be ignored. If you live in an area where landslides are possible, look for these signs:

  • Ground cracks, particularly ones that appear to pull apart
  • Sinking areas or changes in ground level
  • Unexplained leaks in pipes
  • Tilting poles
  • New cracks appearing in a structure
  • New springs or areas where water seems to drain without appearing on the surface

These signs are important to look out for. The first one, ground cracks, are the most obvious. They tend to arcuate and numerous. The largest ones may mark the head of the slide, though that is not a precise indicator of how large a slide may become. Ground cover itself doesn’t prevent deep seated landslides but it can help with smaller surficial slope failures. If you see any of these signs, please contact an engineering geologist or other local official to help assess the likelihood of a failure. Doing so can help prevent injury, loss of life, and property damage.

Mudslides, such as those that recently blocked Interstate 5 in Grapevine Canyon and State Route 58 in Cache Creek Canyon, are more common on steeper slopes with loose material. These tend to happen more commonly in areas which have burned recently, leaving little plant material and a soil that is less porous than it was previously. Those conditions, combined with a heavy rainfall, can turn that material into a thick mud which can easily move larger objects, such as boulders and trucks. As such, these slides can be very dangerous and fast moving.

The California Geological Survey has put together a series of maps to help determine the likelihood of a slope failure. These maps cover most of the metropolitan regions of California and are a great resource. They should, however, only be used as a guideline for potential slope failures. A more exact analysis should be determined through a geological report on your specific location.

Old US 99 at Weldon Summit

US 99, known as “The Old Road” in the Santa Clarita area, has had a varied past. It was first built through this area in 1930 as a three-lane highway. This roadway, known then as the Newhall Alternate, would be the first of many versions of the road through this pass.

This is the last remaining uncovered stretch of the 1930 Newhall Alternate concrete. Motorcycle is on the 1951 alignment.
This is the last remaining uncovered stretch of the 1930 Newhall Alternate concrete. Motorcycle is on the 1951 alignment.

In 1949, the roadway was temporarily widened to four lanes by restriping and adding some paving to the shoulder. This was done as the real work to upgrade the highway wouldn’t commence for a couple of years. Evidence of this widening can still be seen today.

Double white striping from a "temporary" four-lane configuration of the old three-lane concrete. This was done in 1949 as an interim measure before the road was reconstructed as an expressway in 1951.
Double white striping from a “temporary” four-lane configuration of the old three-lane concrete. This was done in 1949 as an interim measure before the road was reconstructed as an expressway in 1951.

In 1951, US 99 was realigned and finally upgraded to an expressway, though this would not last long. Just south of this point, the highway was realigned again to accomodate a new freeway from the Tunnel Station Junction (US 6 and Foothill Blvd) to Sepulveda Junction (State Route 7). This freeway still exists today in part and serves as the “Truck Route” through the pass.

North view of the old southbound lanes just south of the summit.
North view of the old southbound lanes just south of the summit.

Starting in 1967 and ending in 1975, the pass was yet again the site of major construction. This time, little of the old highway would be utilized as the new route of Interstate 5 bypassed much of the existing route. Where it didn’t bypass the alignment, it was torn up and completely replaced with the current roadway.

US 99 would, however, serve as the main route one last time following the January 17, 1994 Reseda / Northridge earthquake. Portions of I-5 collapsed during the earthquake, resulting in a need for a quick replacement. The resulting detours created an alignment very similar to the pre-1967 highway, giving motorists (albeit not with joy) a chance to drive old US 99 again. Upgrades were made to the highway through the pass including repaving, guardrail, and a temporary prohibition on left turns. Sadly, for highway historians, this resulted in the loss of the 1951 concrete and some curbing. It is a price to pay to help keep California’s Backbone functioning during a crisis.

Looking northerly toward Gavin Canyon. This was the location where I-5 was temporarily rerouted onto old US 99 in 1994.
Looking northerly toward Gavin Canyon. This was the location where I-5 was temporarily rerouted onto old US 99 in 1994.

Highway Resources Page

I’ve recently added a new section to the socalregion website. I noticed the site was lacking in resources for local roadways. In particular, information on how to contact various local agencies for road projects, logs, and maintenance. With this in mind, I’ve added a new page to help others get their roads fixed and find out more information about those roadways. I’ve called it the “Southern California Highway Resources” page, which can be found on the Southern California Highways page and via this link.