Skip to main content

Interstate 505; a trace of Interstate 5W

While on a recent Bay Area trip I primarily focused on routes I hadn't previously taken or didn't really research much in the past.  One such route was Interstate 505 which as originally conceived was meant to be part of Interstate 5W.


I-505 is a fairly unassuming 33 mile three digit Interstate connecting I-80 near Vacaville in Solano County north to I-5 near Dunnigan in Yolo County.  I-505's most significant claim to fame was that it was approved to be part of I-5W.

The entire route of I-505W was part of Legislative Route Number 90 before the 1964 State Highway renumbering.   LRN 90 was approved by the State Legislature in 1933 according to CAhighways.org.

CAhighways.org on LRN 90

LRN 90 was not a signed highway before the 1964 State Highway renumbering.  The alignment of LRN 90 was far from the straight north/south shot that I-505 is today.  The route of LRN 90 between US 40 near Vacaville and US 99W near Zamora/Dunnigan can be seen on the 1938 State Highway Map.

1938 State Highway Map

The 1935 California Division of Highways Maps of Solano County and Yolo County provided more in depth detail on the original alignment of LRN 90.

1935 Solano County Highway Map

1935 Yolo County Highway Map

By 1946 LRN 90 was straightened to reach US 99W closer to Dunnigan at it's north terminus.

1946 State Highway Map

LRN 90 became far more important during the first proposed Interstate Highway System in 1947.  LRN 90 was selected to become part of I-5W but the 1947 Interstate plans didn't come to fruition.  The next stage in progress regarding LRN 90 came by 1948 when the southern segment connecting to US 40 was straightened.

1948 State Highway Map

The present Interstate Highway system was approved by 1958.  I-5 was run through Central California with the I-5E spur following the corridor of US 99 and I-5W following the corridor below:

-  Modern CA 132 west to I-580.
-  Modern I-580 west to I-80.
-  Modern I-80 east to I-505.
-  Modern I-505 to I-505.

Segments of what is now I-580 were actually signed in field along US 50 as I-5W.  Interestingly what ultimately killed I-5W and I-5E was the 1964 California State Highway Renumbering.  The 1964 Renumbering had several major aims but two of the larger goals were to eliminate long multiplexes and suffixed routes.  LRN 505 appears on the 1964 State Highway Map on what was LRN 90.

1964 State Highway Map

CAhighways has more substantial background on I-5W which can be found below.

CAhighways.org on I-5 and I-5W

According to CAhighways.org I-505 had a temporary signed routing on the path of LRN 90 before 1972.  The entirety of I-505 was completed to freeway standards by 1977.

I-505 can be seen partially complete on the 1975 State Highway Map.  Only the segment of I-505 north from I-80 to CA 128 in Winters was built to full freeway standards. 

1975 State Highway Map 

By the 1977 State Highway Map I-505 is shown completed to freeway standards north to Madison.

1977 State Highway Map

On the 1981 State Highway Map the full route of I-505 is shown at freeway standards.

1981 State Highway Map

With all the above in mind my drive on I-505 wasn't a full one but rather only to CA 128 northbound from I-80 west.   I-505 has a somewhat bland looking junction from I-80.



I-505 is a fairly fast stretch of freeway which opens up immediately to 70 MPH.


Winters is signed as 11 miles to the north on I-505.


North of Putah Creek Road I-505 enters Yolo County.  CA 128/Signed County Route E6 is located off Exit 11 in Winters.






Comments

Popular posts from this blog

Horace Wilkinson Bridge (Baton Rouge, LA)

Standing tall across from downtown Baton Rouge, the Horace Wilkinson Bridge carries Interstate 10 across the lower Mississippi River between West Baton Rouge and East Baton Rouge Parishes. Unusually, the bridge is actually named for three separate people; three generations of Horace Wilkinsons who served in the Louisiana State Legislature over a combined period of 54 years. Constructed in the 1960s and opened to traffic in 1968, this is one of the largest steel bridges on the lower Mississippi. It’s also the tallest bridge across the Mississippi, with its roadway reaching 175 ft at the center span. Baton Rouge is the northernmost city on the river where deep-water, ocean-going vessels can operate. As a result, this bridge is the northernmost bridge on the river of truly gigantic proportions. Altogether, the bridge is nearly 2 ½ miles long and its massive truss superstructure is 4,550 ft long with a center main truss span of 1,235 ft. The Horace Wilkinson Bridge is one of the largest

Veterans Memorial Bridge (Gramercy, LA)

When we think of the greatest engineering achievements and the greatest bridges of North America, we tend to focus on those located in places familiar to us or those structures that serve the greatest roles in connecting the many peoples and cultures of our continent. Greatness can also be found in the places we least expect to find it and that 'greatness' can unfortunately be overlooked, due in large part to projects that are mostly inconsequential, if not wasteful, to the development and fortunes of the surrounding area. In the aftermath of the George Prince ferry disaster that claimed the lives of 78 people in October 1976 in nearby Luling, LA, the state of Louisiana began the process of gradually phasing out most of its prominent cross-river ferry services, a process that remains a work in progress today. While the Luling-Destrehan Ferry service was eliminated in 1983 upon completion of the nearby Hale Boggs Memorial Bridge, the ferry service at Gramercy, LA in rural St.

Sunshine Bridge (Donaldsonville, LA)

Located about halfway between Baton Rouge and New Orleans in southern Louisiana, the Sunshine Bridge spans the lower Mississippi River near the city of Donaldsonville as part of the longer Louisiana Highway 70 corridor, which connects Interstate 10 and Airline Highway (US 61) with US 90 in Morgan City. In the years following World War II, the only bridges across the lower Mississippi River in Louisiana were located in the area of the state’s two largest cities – Baton Rouge and New Orleans. Postwar agricultural and industrial development along the river in this region led to the planning of a series of infrastructure projects in southern Louisiana that were aimed at spurring this development and modernization of the Delta region. One of these projects was known as the Acadian Thruway and was developed in the 1950s as a toll road intended to connect greater New Orleans with Lafayette and points west while providing a high-speed bypass of the Baton Rouge metro area. The Thruway, which