 State Route 84 | ||||
|---|---|---|---|---|
 SR 84 highlighted in red, with the relinquished portions inWest Sacramento in pink | ||||
| Route information | ||||
| Maintained byCaltrans | ||||
| Length | 96 mi[1] (154 km) | |||
| Tourist routes |  Niles Canyon Road betweenSR 238 inFremont andI-680 nearSunol | |||
| Restrictions | Special restrictions[2]
| |||
| Section 1 | ||||
| West end |  SR 1 atSan Gregorio | |||
| Major intersections | ||||
| East end |  I-580 inLivermore | |||
| Section 2 | ||||
| South end |  SR 12 inRio Vista | |||
| North end | Near Levee Access Road at the southern city limits ofWest Sacramento | |||
| Location | ||||
| Country | United States | |||
| State | California | |||
| Counties | San Mateo,Alameda,Solano,Yolo,Sacramento | |||
| Highway system | ||||
| ||||
State Route 84 (SR 84) is astate highway in theU.S. state ofCalifornia that consists of two unconnected segments, one in theSan Francisco Bay Area and the other primarily in theSacramento–San Joaquin River Delta area.
The first section is an east–westarterial road running fromSR 1 inSan Gregorio toMenlo Park, across theDumbarton Bridge throughFremont andNewark and ending atI-580 inLivermore. The segment between Marsh Road and the Dumbarton Bridge has been upgraded to anexpressway and is known as the Bayfront Expressway. The segment from the eastern end of the Dumbarton Bridge to the interchange with I-880 has been upgraded to a freeway.
The other section is a north-south arterial road that begins atSR 12 inRio Vista, passes throughRyer Island (where it connects toSR 220), and ends inWest Sacramento. TheRyer Island Ferry provides the crossing over Cache Slough from Rio Vista to Ryer Island. The ferry is a diesel-powered boat operated byCaltrans, and is in operation twenty-four hours per day and charges no toll.
There are no plans to connect the two unconnected segments of SR 84 at this time. A proposed toll road called theMid-State Tollway along the proposed route was abandoned in 2001 due to local opposition.
The route begins atSR 1 on thePacific coast nearSan Gregorio. It then heads northeast throughSan Mateo County, following San Gregorio Road and La Honda Road and crossing theSanta Cruz Mountains. As it entersWoodside, it intersectsSR 35, also known as Skyline Boulevard. From the juncture of La Honda Road with Portola Road to US 101 it follows Woodside Road. It then passes through downtown Woodside. After intersectingI-280, it entersRedwood City, where it intersectsSR 82, which carriesEl Camino Real through the South Bay. A few miles later, it interchanges withUS 101, which it overlaps for a few miles.
Upon routing eastward, it enters the city ofMenlo Park as anexpressway, called theBayfront Expressway, which features traffic signals at Menlo Park streets, atdriveways servingFacebook headquarters, and at intersections withSR 114 andSR 109. The Marsh Road intersection, in 2013, was the site where a car struck cyclist Sam Felder , a Facebook employee, after he ran a red light. He died 3 months later.[3] The SR 114 (Willow Road) intersection was the site of a car crash in which authorDavid Halberstam was killed on April 23, 2007.[4]
SR 84 then becomes a freeway at the south end of San Mateo County as it crosses as theDumbarton Bridge over theSan Francisco Bay. Midway over the bridge, it entersAlameda County. InAlameda County, it runs northward through the city ofNewark, where it begins a concurrency southwards withI-880 for about one mile. Both interchanges with I-880 arepartial cloverleaf interchanges. Upon separation, however, the route is not built to freeway standards as it enters the city ofFremont, following the streets of Thornton Avenue, Fremont Boulevard, Peralta Boulevard, and Mowry Avenue, which after, it has a short concurrency northwards withSR 238.
SR 84 then leaves Fremont through the historicSunol Valley. Parts of the valley are extremely narrow and are referred to asNiles Canyon; this part of the route is officially ascenic route.[5] The section is known asNiles Canyon Road, and there are legends of aNiles Canyon ghost inhabiting the area.[6]
After exiting the valley, it begins an overlap withI-680. After separating, it runs through Vallecitos Valley. It then goes over grasslands until it reaches a pass, then enters the city ofLivermore with Ruby Hill development on the left. SR 84 then runs along Isabel Avenue until it meetsI-580, as the end of its southern section. SR 84 is unconstructed from I-580 toSR 12.
The second section of SR 84 starts inRio Vista at SR 12. It then follows theRyer Island Ferry, which carries the route across theCache Slough. When it leaves the ferry, it intersectsSR 220. It continues northward and meets the end of state maintenance at theWest Sacramento city limit, about six miles east of an intersection withCR E19. It then enters the city ofWest Sacramento inYolo County. It then interchanges withI-80 Business, also signed asUS 50. As it continues northward, it ends atI-80. From north of West Sacramento, SR 84 has been relinquished and was given to the city of West Sacramento in 2003.[7]
SR 84 is part of theCalifornia Freeway and Expressway System,[8] and from I-280 to the eastern Fremont city limits and from the southern terminous of Isabel Avenue in Livermore to I-580 is part of theNational Highway System,[9] a network of highways that are considered essential to the country's economy, defense, and mobility by theFederal Highway Administration.[10] SR 84 is eligible for theState Scenic Highway System,[11] and is designated as a scenic highway by theCalifornia Department of Transportation from SR 238 to I-680 in Alameda County,[12] meaning that it is a substantial section of highway passing through a "memorable landscape" with no "visual intrusions", where the potential designation has gained popular favor with the community.[13]
Until recent years, all of CA-84 consisted of narrow, two-lane roads in California. This has remained almost unchanged except for urban areas and the CA-84 widening project in the Tri-Valley.
Route 84 is legally defined to continue from I-580 toSR 4 inAntioch, but there are currently no plans in place to bridge the gap at this time. A plan to build a $600 milliontoll road called theMid-State Tollway along the proposed route was suspended in 2001 due to local opposition.[14]
In the late 2000s and 2010s, a widening project began on Route 84 from I-680 near Sunol to I-580 in Livermore. This included a better connection between Stanley Boulevard and Isabel Avenue.[15] The project was to be done in five phases:
Costs were estimated to be between $400 and $500 million.[16]
As of mid 2019, phases 1, 2, 3 and 4 are complete. This still leaves the southern section of CA 84 in its original condition.
Both the Ryer Island Ferry and theHoward Landing Ferry alongRoute 220 are the only state-run ferries, and there are no plans to replace them with bridges due to the low traffic numbers around Ryer Island.[17][18][19] The only road bridge connecting Ryer Island is on its north side, which results in longer commutes for residents if one or both ferries shutdown.[20]
Except where prefixed with a letter,postmiles were measured on the road as it was in1964, based on the alignment that existed at the time, and do not necessarily reflect current mileage. R reflects a realignment in the route since then, M indicates a second realignment, L refers to an overlap due to a correction or change, and T indicates postmiles classified as temporary (for a full list of prefixes, seeCalifornia postmile § Official postmile definitions).[21] Segments that remain unconstructed or have been relinquished to local control may be omitted. The numbers reset at county lines; the start and end postmiles in each county are given in the county column.
| County | Location | Postmile [21][1][22] | Exit [23] | Destinations | Notes | ||
|---|---|---|---|---|---|---|---|
| San Mateo SM 0.00-R30.15 | San Gregorio | 0.00 | SR 1 –Half Moon Bay,Santa Cruz | Southwest end of SR 84 | |||
| Woodside | 14.95 |  SR 35 (Skyline Boulevard) –San Francisco,Santa Cruz | |||||
| 21.54 |  I-280 (Junipero Serra Freeway) –San Francisco,San Jose | Interchange; I-280 exit 25 | |||||
| Redwood City | 24.70 |  SR 82 (El Camino Real) | Interchange | ||||
| 5.72 5.39[N 1] |   US 101 north (Bayshore Freeway) / Seaport Boulevard –San Francisco | Interchange; west end of US 101 overlap; US 101 exit 408 | |||||
| Western end of freeway on US 101 | |||||||
| Menlo Park | 3.59[N 1] R25.81 | Eastern end of freeway on US 101 | |||||
 US 101 south (Bayshore Freeway) / Marsh Road –San Jose,Atherton | Interchange; east end of US 101 overlap; US 101 exit 406 | ||||||
| R27.66 | Willow Road (SR 114) | ||||||
| R28.19 | University Avenue (SR 109) | ||||||
| | Western end of freeway | ||||||
| | — | Ravenswood,S.F. Bay National Wildlife Refuge | |||||
| San Francisco Bay | R29.25– R0.00 | Dumbarton Bridge (westbound toll only) | |||||
| Alameda ALA R0.00-R28.63 | Newark | R3.75 | 36 | Thornton Avenue, Paseo Padre Parkway | Last free exit for westbound traffic | ||
| R4.88 | 37 | Newark Boulevard, Ardenwood Boulevard | |||||
| R6.01 10.30[N 2] | 38 |   I-880 north (Nimitz Freeway) / Decoto Road –Oakland | Interchange; west end of I-880 overlap; I-880 exit 21; formerSR 17 north | ||||
| Fremont | 8.84[N 2] 6.92 | Eastern end of freeway on I-880 | |||||
 I-880 south (Nimitz Freeway) / Thornton Avenue –San Jose | Interchange; east end of I-880 overlap; I-880 exit 19; formerSR 17 south | ||||||
| 10.82 3.31[N 3] |   SR 238 south (Mission Boulevard) –San Jose | West end of SR 238 overlap | |||||
| 3.64[N 3] 10.83 |  SR 238 north (Mission Boulevard) / Niles Boulevard –Hayward,Union City | East end of SR 238 overlap | |||||
| Sunol | 16.93 | Sunol (Main Street) | Interchange; eastbound exit and westbound entrance | ||||
| | 17.99 R11.04[N 4] |  I-680 south / Calaveras Road –Fremont,San Jose | Interchange; west end of I-680 overlap; I-680 north exit 21A, south exit 21 | ||||
| Western end of freeway on I-680 | |||||||
| | R11.85[N 4] 17.99 | — | I-680 north –Walnut Creek,Sacramento | East end of I-680 overlap; I-680 north exit 21B, south via a U-turn at exit 21 | |||
| | | Eastern end of freeway | |||||
| Pleasanton | 23.56 | Vallecitos Road –Downtown Livermore | Former SR 84 east | ||||
| Livermore | R26.22 | Stanley Boulevard | Interchange | ||||
| | I-580 / Isabel Avenue to Portola Avenue –Oakland,Stockton | Interchange; northeast end of southwestern segment of SR 84; I-580 exit 51 | |||||
| Gap in route | |||||||
| Solano SOL 0.13-13.67 | Rio Vista | 0.13 | SR 12 / Front Street –Lodi,Fairfield,Rio Vista | Interchange; south end of northern segment of SR 84 | |||
| | 2.49 |  Ryer Island Ferry acrossCache Slough | |||||
| | 7.25 |   SR 220 east –Ryde | Western terminus of SR 220 | ||||
| Yolo YOL 0.00-24.05 | | 9.53 |   CR E19 east (Clarksburg Road) –Clarksburg | Western terminus of CR E19 | |||
| West Sacramento | 15.69 | North end of state maintenance atWest Sacramento city limit | |||||
| R21.78 |  US 50 (I-80 BL,I-305) –San Francisco,Sacramento | Interchange; formerI-80; US 50 / I-80 BL exit 3 | |||||
| 21.84 | ToCapitol Mall (SR 275,Cabaldon Parkway) | Interchange; formerUS 40 /US 99W (1955–1964); formerly Tower Bridge Gateway | |||||
| 22.06 | West Capitol Avenue | FormerUS 40 /US 99W (1926–1955) | |||||
| 22.68 | Sacramento Avenue, Kegle Drive | Sacramento Avenue is formerSR 16 east | |||||
| 23.47 | Sunset Avenue –Woodland | FormerSR 16 west | |||||
| 24.05 |    I-80 toI-5 –Reno,San Francisco | Interchange; north end of SR 84; formerI-880; I-80 exit 83; access to I-5 via I-80 east | |||||
| 24.05 | Reed Avenue | Continuation beyond I-80 | |||||
| 1.000 mi = 1.609 km; 1.000 km = 0.621 mi | |||||||
