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Unsigned State Route 51

Click here for a key to the symbols used. An explanation of acronyms may be found at the bottom of the page.

Routing Routing

Rte 51 Past and PresentBusiness Route Shield From Route 50 in Sacramento to Route 80 east of Sacramento. Per SHC Section 351.1: Route 51 is signed as Interstate Business Loop 80.

Post 1964 Signage History Post 1964 Signage History

Post-1964 Legistlative Route Graphic In 1963, Route 51 was defined to run from Route 5 to Route 5 near Santa Ana. That route was part of LRN 2. It ran along Orangewood Avenue from I-5 east to Main Street, passing south of what is now Edison Field, and then along Main Street south back to I-5 (thanks to Calvin Sampang for hunting that out). The routing was deleted in 1965 by Chapter 1372.

State Shield In 1981, Chapter 292 defined the current routing. This is a former segment of I-80 that was bypassed by new construction for I-80. The original plan, however, was to have this segment, as well as the segment from US 50 to I-80 (legislatively US 50, signed Business Route 80) upgraded to proper interstate standards, and have the current I-80 routing be I-880. But that didn't happen (see I-80 for details), thus resulting in the creation of Route 51 (Business Route 80).

With respect to this segment, during the 1964 State Highway renumbering Route 80 was assigned onto US 99E to US 99, indicating it was planned as the future route of I-80, with future I-880 (current I-80) bypassing Sacramento to the north. By 1965 a new freeway grade is completed to US 99 and I-80 is co-signed into Sacramento on US 99E. In 1966 a new planned alignment of I-80 appears next US 99E/I-80 from the American River north to the planned I-880. In 1967 US 40, US 99E, and US 99W all disappear from California. US 99 is reassigned as CA 99. By 1969, I-80 is shown complete through downtown Sacramento but the former alignment of US 99E is shown as Temporary I-80. In 1981 the planned alignment of I-80 was cancelled by the State Legislature (and the planned I-880 became I-80). This action led to the creation of Route 51 and the legislative definition that it must be signed as the Business Route 80. On the 1982 state highway map, I-80 is shown on the (Legislative) Route 51 routing, and I-880 is shown on (Legislative) Route 80 routing. By 1986, Business Route 80 appears on (Legislative) Route 51 (with a loop back to I-80 along (Legislative) Route 50 (US 50)), and I-880 has become I-80. By 2015, Caltrans was deemphasizing Business Route 80, and the (Legislative) Route 50 section was signed as US 50; however, thanks to the legislative requirement Route 51 was still signed as Business Route 80. This paragraph was condensed from Tom Fearer's blog post on the subject; said blog posts has links to the state highway maps and annotated insets showing all of this.
(Source: Gribblenation Blog: California State Route 51; failed Interstate 80 on the Capitol City Freeway, the I–80 Business Loop, and former US 40/99E, 10/18/2018)

Pre 1964 Signage History Pre 1964 Signage History

Before the construction of the US-50 and I-80 freeways through Sacramento, this route was:

What eventually became Route 51 was originally defined as a State Highway during the 1909 First State Highway Bond Issue. Said highway was to run from Sacramento north to the Oregon State Line and eventually would be assigned LRN 3. LRN 3 north out of Sacramento ran from L Street; along 16th Street over the American River to Del Paso Boulevard, then along Del Paso Boulevard to El Camino Avenue to Auburn Boulevard, and then along Auburn Boulevard towards Roseville. When the US Route system was finalized in 1926 the route of LRN 3 north out of Sacramento was assigned US 40 and US 99E. US 40/US 99E can be seen on LRN 3 north out of Sacramento in the 1934 City Insert for Sacrament on the State Highway Map. In 1944 the first major change to LRN 3 in the Sacramento Area appears with a planned bypass of North Sacramento. By 1948 the North Sacramento Bypass was completed. The North Sacramento Bypass would eventually became part of Route 160 on the North Sacramento Freeway in addition to Route 51 on the Capitol City Freeway north of the American River. By 1951 a new planned route for US 99E to cross the American River appears on the City Insert of Sacramento. This newly planned route of US 99E would be assigned to pre-existing LRN 98. By 1955 a fully planned routing of US 99E over the American River to US 50 and the mainline US 99 appears on the City Insert for Sacramento. By 1956 the new US 99E alignment was completed from US 40 north of the American River south to US 99. US 99E utilized 29th and 30th Street in one-way configurations to reach US 99. This paragraph was condensed from Tom Fearer's blog post on the subject; said blog posts has links to the state highway maps and annotated insets showing all of this.
(Source: Gribblenation Blog: California State Route 51; failed Interstate 80 on the Capitol City Freeway, the I–80 Business Loop, and former US 40/99E, 10/18/2018)

The freeway construction began in May 1950, but delays due to material shortages and weather put of major construction until 1952. The first 2.9 mile 4-lane stretch opened on May 12, 1955. Lots of construction details can be found on Joel Windmiller's Elvas Freeway site.

Pre-1964 State Shield Route 51 was not defined as part of the initial state signage of routes in 1934. It is unclear what (if any) route was signed as Route 51 between 1934 and 1964.

Status Status

Business Loop 80 (Cap City Freeway) vs. Route 51

This is the existing section of Business Loop 80 between the US-50/Route 99 interchange and I-80. Construction was done on a section near the north end of the I-80/Business Route 80 interchange to replace what is known as the Elvas Freeway, since it is currently only a two lanes in each direction freeway for a portion near Cal Expo. The section that was built is currently being used by Sacramento RTD to operate their light rail system. This is not consistantly signed, although you can see the designation on the mileage markers.

In September 2015, it was reported that Caltrans was resigning the routes in Sacramento to de-emphasize Business Route 80 except where legislatively mandated (i.e., along Route 51). This is based on a desire to simplify things and just sign US 50 as one route and not a multitude of routes, especially as more and more people are referring to the joint US 50/Business Route 80 multiplex as simply US 50. However, the legislative description for Route 51 mandates that it be signed as Business Route 80; the legislative description of Route 50 includes no such requirement. So basically, Business Route 80 is becoming a Business spur, but there's no plans to update the signing to reflect such a change. The Capital City Freeway name will be emphasized on Route 51 and only Route 51.

Capital City Freeway Project

In September 2017, Caltrans launched a public webiste for the Capital City Freeway Project. The primary objective of the proposed $575 million project from J Street to Exposition Boulevard over the American River is to extend the existing bus/carpool lanes, widen about a three-mile stretch of highway to accommodate new bus/carpool lanes for both directions, construct auxiliary lanes and construct a new Class I bike path on the American River Bridge. Route 51 (Business Route 80) and adjacent surface streets have become the most congested corridor in the region. In 2016, the Cap City Freeway experienced more than 2,050,000 annual hours of delay at a $27.5 million cost to users and had five of the region’s top 10 bottlenecks. The project is currently in the Engineering and Environmental Studies phase.

In August 2013, it was reported that Caltrans is pursuing plans to close the E Street on ramp in east Sacramento (apx. 51 SAC 1.454). This will permit them to squeeze another mile long lane onto the freeway from J Street to the bridge over the American River. The eastbound side of the freeway currently drops from five lanes to three in the space of a quarter mile near E Street, making that stretch of freeway the worst pinch point in the region. The reconfiguration, considered minor at a cost of $6 million, would allow the state to extend the fourth lane another mile to nearly the foot of the American River bridge. Although Caltrans has legal authority to close the ramp, Jones said the agency is seeking input from the city and will check in with area residents as well. Caltrans ultimately will have to do an environmental analysis to justify the change. The ramp closure date is likely three years away, officials estimate.

American River Bridge Vicinity Improvements (PPNO 6402 3-Sac-51 2.6/3.0, PPNO 6409 3-Sac-51 ~1.04/4.07)

In December 2015, it was reported that Caltrans has begun laying the groundwork for a $700 million freeway widening from midtown to the junction with I-80. That includes widening the American River bridge (apx. 51 SAC 2.696) to add a new multi-use lane in each direction, as well as building wider shoulders for stalled cars to pull over, a separate lane on the bridge for cyclists and pedestrians, and other improvements. The proposed project area is 8 miles long. Caltrans officials say the project is so big and the funding sources so uncertain that it may not happen for a decade. A few years ago, Caltrans considered simply closing the E Street onramp and adding a brief extra lane, based on a traffic analysis that showed that would ease the bottleneck. But as traffic increased post-recession, state and city officials concluded they need to take “a much bigger bite of the apple.” Caltrans and Sacramento planners say they expect new state transportation funds to materialize over time, and more federal funds to be available for multimodal projects that reduce greenhouse gas emissions and other pollutants. SACOG this month allocated $9 million to Caltrans for project planning. That includes defining the scope of the project, conducting environmental studies and obtaining permits and other approvals, then applying for grants when they become available. It also involves working with state, federal and local agencies, advocacy groups and private companies such as Union Pacific. The state says it is looking at expanding in two phases. The first involves a variety of changes, most notably a new lane in each direction from J Street on the south end to Arden Way on the north side of the river. The second phase involves working from Arden Way east to I-80. Buses and carpools will have exclusive rights to the new lanes. Those high-occupancy vehicle, or HOV, lanes revert to “mixed flow” for solo drivers to use during nonpeak hours. The state is committed to making the rebuilt Capital City Freeway “multimodal,” most notably by adding a bike and pedestrian travelway on the bridge over the river, separated from cars, to connect to existing bike trails on both sides of the river. The state also would change freeway ramps to make them more accessible for buses and safe to cross for cyclists and pedestrians. Caltrans, meanwhile, plans to spend $137 million to scrape and replace the bridge deck and do other maintenance and repair work, much like it did on the Fix 50 project last year. That work is expected to occur in about five years and will help set the bridge up for the widening project to come later.
(Source: Sacramento Bee, 12/25/2015)

In October 2015, the CTC approved the following long lead SHOPP funding: 3-Sac-51 2.6/3.0 Route 51 (Business Route 80) In the city of Sacramento at the American River Bridge No.24-0003. Widen and replace bridge deck. PAED: 08/01/2018 R/W: 02/01/2020 RTL: 05/01/2020 CCA: 10/01/2022 Costs: $1,000K (R/W); $105,300K (C). Completion FY19/20. Supporting Costs: PA & ED $4,340K; PS & E $10,130K; RW Sup $360K; Con Sup $16,120K; Total $30,950K.

51/B80 American River PlanningIn September 2017, it was reported that Caltrans is looking at four project options to unclog the bottleneck near the American River Bridge (apx. 51 SAC 2.696). Three involve widening the existing bridge to add lanes. A fourth proposal is notably different. The state is considering building a new bridge a few hundred feet to the northwest. The new bridge alignment would eliminate the tight freeway curve that exists on the south side of the river, a curve that is sharper than current freeway standards advise. But it would cut through land planned to be part of Sutter’s Landing Regional Park. Caltrans then likely would tear down the current bridge. But officials said there may be a scenario where that bridge would remain in place if, for instance, Sacramento officials felt they had some other use for it. All four options could include a reversible lane, allowing cars to travel in different directions at different points during the day. The expansions also would include carpool lanes and a separate area on the bridge for bicyclists and pedestrians. The 3.4-mile work area would start at J Street on the south side of the river and run just beyond Arden Way on the north side. The total cost of the project likely will top a half-billion dollars. Caltrans has launched a website to provide more information. The project is so massive that the planning, environmental studies, engineering and fund-gathering process likely will take six years. That means construction will not begin before 2023, and the project won’t be finished for another four years after that. Caltrans officials had for years shied away from committing to the project, partly because of the cost, but also because most policymakers and planners in the Sacramento region agree that widening freeways generally has the adverse effect of inviting people to drive more, which ends up causing more long commutes and more congestion in the long term. But traffic analyses by the Sacramento Area Council of Governments indicate that unblocking the Capital City Freeway would have positive regional effects that reach beyond Sacramento County. Funding is not yet set. Caltrans and Sacramento planners say they expect state transportation funds to materialize over time, and more federal funds to be available for multimodal projects that reduce greenhouse gas emissions. There also continues to be talk of a transportation sales tax measure on the 2018 or 2020 ballots to raise funds for road fixes that could provide money for the project.
(Source: Sacramento Bee 9/25/2017)

In January 2018, the CTC amended the SHOPP as follows: 03-Sac-51 2.6/3.0 2.0/3.5. Route 51/Business Route 80 In the city of Sacramento, at the American River Bridge No. 24-0003 from north of B Street Underpass to north of Exposition Boulevard Overcrossing. Widen and replace bridge deck. Total Cost: $137,250,000. $163,940,000. Construction phases not yet authorized.
(Source: CTC Agenda, January 2018, Agenda Item 2.1a(1))

The 2018 STIP, approved at the CTC March 2018 meeting, appears to allocate Advance Program Development Element (APDE) funding of $7.9M for environmental and planning for PPNO 6409, Corridor Improvements, J St-Arden Way on Route 51.

In October 2018, Joe Rouse noted on AAroads: "There are plans to widen Business Route 80 (Route 51) between E Street and roughly Arden Way. This proposal came as a result of a study to close the E Street ontamp to eastbound Business Route 80 and extend the 4th lane that currently drops around F Street up to the American River Bridge. This lane drop is the worst bottleneck on the State highways in the city. Analysis showed that this modification would not help traffic flow and the City of Sacramento pushed for a broader study on improvements to the whole Route 51 corridor. It led to a proposal to widen Route 51 over its entire length but the focus eventually was reduced to the portion between E Street and Arden Way, with the portion between Arden and I-80 to be looked at later. These improvements include a new bridge over the American River. The early study looked at widening the existing bridge but there are substantial deck repairs needed to that hurdle and so I think they came to the conclusion that it was more cost effective to replace it. The new bridge would sit between the SP railroad bridge and the existing bridge and would cross over the railroad tracks, eliminating the narrow Elvas Junction underpass. The new alignment would include HOV lanes, and an HOV flyover would be just through the Arden interchange to avoid conflict with the Arden onramp to westbound Business Route 80, which is a left hand entrance."
(Source: Joe Rouse on AAroads, 10/21/2018)

In March 2020, the CTC approved the 2020 STIP, which included $8,400K in prior programming for PPNO 6409 "Corridor Improvements, J St-Arden Way (APDE)"
(Source: March 2020 CTC Agenda, Item 4.7, 2020 STIP Adopted 3/25/2020)

The 2020 SHOPP, approved in May 2020, included the following Bridge Preservation item of interest (carried over from the 2018 SHOPP): 03-Sacramento-51 PM 2.0/3.5 PPNO 6402 Proj ID 0312000054 EA 3F070. Route 51 (Business Route 80) in the city of Sacramento, at the American River Bridge No.24-0003 from north of B Street Underpass to north of Exposition Boulevard Overcrossing. Widen and replace bridge deck.  This is a Construction Manager/General Contractor (CMGC) project. Programmed in FY21-22, with construction scheduled to start in March 2022. Construction capital and construction support phases are not programmed. Total project cost is $163,940K, with $125,000K being capital (const and right of way) and $38,940K being support (engineering, environmental, etc.).
(Source: 2020 Approved SHOPP a/o May 2020)

There has been an ongoing project to widen the connector ramp from westbound I-80 to westbound Business Route 80 (Route 51) northeast of Sacramento (apx. 51 SAC 8.535). The connector is currently 2 lanes, and is a huge bottleneck for the morning commute. One extra lane is being added. This meant widening the bridge that carries WB Business Route 80 over WB I-80 as well as eliminating the second exit to Watt Avenue (there is already a Watt Ave exit right after the ramp split).

Commuter Lanes Commuter Lanes

HOV lanes are planned for the segment from the US 50/Route 51/Route 99 separation bridge to N Street.

Naming Naming

Previously, this route had the following names:

  1. The portion of this route from Route 160 to Route 50 was named the "Elvas Freeway".
  2. The portion of this route between Route 160 and the Marconi Curve was named the "North Sacramento Freeway". North Sacramento refers to the community of North Sacramento, which was originally an independent city. North Sacramento was originally a suburb of Sacramento, developed in the 1940s north of the American River. It was annexed in 1964, but the city name is still used in some mailing addresses. Recently, North Sacramento has become the urban arts district of Sacramento (and also gained the moniker of "Uptown Sacramento"). Sacramento refers to the City of Sacramento CA, which is based off of the name of the main river in the city. The Spanish name, "Holy Sacrament," was applied to the Feather River in 1808; it was later assumed that the lower Sacramento was the same stream. In 1817 the two main rivers of the valley were recorded as Sacramento and San Joaquin rivers, but the course of the former was not identified with the name until the 1830s. The city was laid out in 1848-1849 and named after the river by John A. Sutter, Jr., and Sam Brannan. The county, one of the original 27, was named in 1850.
  3. This route has been known as the "29/30 Freeway", based on it crossing over 29th and 30th Streets in Sacramento.
  4. At one time, the portion between the Marconi Curve and Route 80 was named the "Roseville Freeway".

Capital City Freeway (Rte 51)In 1996, the Sacramento Regional Planning Authority (SACOG) decided to name the entire Interstate Business Route 80 freeway as the "Capitol City Freeway".
(Image source: AARoads)

Classified Landcaped Freeway Classified Landcaped Freeway

The following segments are designated as Classified Landscaped Freeway:

County Route Starting PM Ending PM
Sacramento 51 0.00 1.71
Sacramento 51 4.05 4.41
Sacramento 51 5.20 5.84
Sacramento 51 5.95 6.18
Sacramento 51 6.28 6.63
Sacramento 51 6.63 7.74
Sacramento 51 7.74 7.85
Sacramento 51 7.85 8.06
Sacramento 51 8.30 8.86

Exit Information Exit Information

Other WWW Links Other WWW Links

Freeway Freeway

[SHC 253.1] Entire route.

Blue Star Memorial Highway Blue Star Memorial Highway

The portion of this route that is former US 40 was designated as a "Blue Star Memorial Highway" by Senate Concurrent Resolution 33, Ch. 82 in 1947.

Statistics Statistics

Overall statistics for Route 51 (Business Route 80):

Pre-1964 Legislative Route Pre-1964 Legislative Route

The route that was to become LRN 51 was first defined in the 1919 Third Bond Act as the route from Santa Rosa to Shellville. In 1933, the route was extended from Sebastopol to [LRN 1] near Santa Rosa. In 1935, the route was codified into the highway code as:

"[LRN 104] near Sebastopol to [LRN 8] at Shellville via Santa Rosa"

In 1937, Chapter 841 changed the terminus of the route to Sears Point from Shellville.In 1951, the route was extended on both ends: the origin was changed to "[LRN 56] near Valley Ford", and the terminus was changed to "[LRN 8] near Sonoma". Signage was as follows:

  1. Between Valley Ford on Route 1 (LRN 56) and Sebastopol on Route 12 (LRN 104): The route was unsigned. It is present-day unconstructed Route 12. Before 1964, Route 12 was signed between Sebastopol and Route 1 along the present-day Route 116 (LRN 104).
  2. Between Sebastopol and cosigned Route 12/Route 37 (now the Route 121/Route 37 junction) 1 mi W of Schellville: Signed as Route 12.

Confusion between the LRN and the signed route may be the source of the rumors that between the late 1960s to the late 1970s, there was a proposed Route 51 that was an (unconstructed) bypass in the Sonoma Valley around the towns of Boyes Hot Springs and Sonoma, that basically followed the alignment of Arnold Drive, on the West side of the valley.

Acronyms and Explanations:

Back Arrow Route 50 Forward Arrow Route 52

© 1996-2020 Daniel P. Faigin.
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