California Highways:
www.cahighways.org

From Route 101 in Eureka to Route 101 in Arcata via the Humboldt Bay Bridge and the Samoa Peninsula.

In 1963, Chapter 1898 defined Route 255 as “Route 101 in Eureka across Humboldt Bay to the Samoa Peninsula” (note: this act added the same route as LRN 294, but that change did not take effect)

In 1970, Chapter 881 extended the route: “Route 101 in Eureka across Humboldt Bay to the Samoa Peninsula to Route 101 near Arcata via the Humboldt Bay Bridge and the Samoa Peninsula” Chapter 1473 that year also redefined the route, but made no changes.

In 1994, Chapter 1220 clarified the routing: “Route 101 in Eureka to Route 101 in near Arcata via the Humboldt Bay Bridge and the Samoa Peninsula”

This route would have been LRN 294, defined in 1963, but that was overtaken by events.

Prior to Route 255 automotive access to the Samoa Peninsula was either via ferry or taking a long drive around Arcata Bay.  The Samoa Peninsula traditionally has been the head of what was until recent decades a large lumber industry in Humboldt County.
(Source: Gribblenation Blog "California State Route 255")

In mid-January 2012, residents of the community of Manila (~ HUM 2.048 to HUM R5.087) installed signage at both entrances to Manila off Route 255 urging motorists to drive safely. Route 255 divides Manila in half. The Pacific Ocean, the beach and dunes, community center, Manila Dunes Recreation Area, the Humboldt Coastal Nature Center and Family Resource Center lie west of the highway. Half of Manila’s population, two churches, the Manila Park and access to Humboldt Bay lie to the east. It is difficult to cross the highway safely because of the high rate of speed of oncoming vehicles and also because of the curves on Route 255 at the Dean Avenue/Pacific Boulevard and the Young Lane/north Peninsula Drive intersections. Manila residents have expressed their safety concerns to representatives of Caltrans at least since the 1970s.
(Source: Arcata Eye, 1/13/2012)

Reconnecting Arcata

In March 2024, it was reported that Governor Gavin Newsom has announced a pilot program to reconnect three communities historically divided by transportation infrastructure in California. The Reconnecting Communities: Highways to Boulevards grant program will increase access and traveling options in underserved and underinvested neighborhoods in Arcata, South San Francisco and southeast San Diego/National City. The pilot program, initially proposed in the Climate Action Plan for Transportation Infrastructure, seeks to convert underused highways that divide underserved communities into multimodal corridors and vibrant public spaces. The Reconnecting Arcata project seeks to address mobility, accessibility, and equity challenges in this rural area caused by three state highways (US 101, Route 255, and Route 299) through a comprehensive, community-driven planning process. Key solutions may include a new transit center, potential freeway cap or new crossings, and expanded walking and biking options. The state highway system created barriers to Arcata neighborhoods and nearby  communities. Bridging this gap would help improve public health while providing more alternative transportation options. Caltrans will assist the selected communities in working from concept to project delivery on a community-driven vision to reconnect their neighborhoods. This includes helping pilot communities to obtain additional grant support for project completion, including the application for the federal Reconnecting Communities and Neighborhoods Grant Program.
(Source: Cal Poly Humboldt, 3/14/2024)

New Navy Base Road Roundabout (~ HUM 2.018)

In February 2026, it was reported that Caltrans was holding public open houes about the proposed New Navy Base Road Roundabout Project. The project would add a quick-build, modular roundabout at the New Navy Base Road intersection as part of a safety program aimed at reducing severe crashes while maintaining efficient access for trucks, freight, and local traffic. Construction is currently planned for summer 2027.
(Source: Caltrans District 1 on FB, 2/20/2026)

Eureka/Arcta Restoration Project for Mitigation (HUM 6.0 to 7.6)

The 2018 STIP, approved at the CTC March 2018 meeting, appears to allocate funding for PPNO 2389, 01-HUM-255 6.0/7.6, the Eureka/Arcta Restoration Project for Mitigation - 3 Parcels (an offshoot of PPNO 0072 on US 101). This is in the vicinity of Eureka & Arcata along Route 255. Construct a wetland restoration project including three parcels as off site mitigation for parent project PPNO 0072, including wetland restoration consisting of freshwater wetland expansion, muted tidal restoration of salt marsh habitat, or a full-tidal restoration of salt marsh habitat. This restoration project will serve as mitigation for the parent project, EA 36600, the US 101 Eureka to Arcata Corridor Improvement Project. The parcels are:

• Parcel 1 - The 78-acre Demello parcel is located west of the City of Arcata, at the end of Lanphere Road (Assessor’s Parcel Number (APN) 506-029-114). The parcel was selected in part, because of its location adjacent to the United States Fish and Wildlife Service (USFWS) Humboldt Bay National Wildlife Refuge’s Lanphere and Ma-le’l Dunes Units.
• Parcel 2 - The second parcel, known as the Samoa parcel is located just west of the City of Arcata, between Route 255 and Old Samoa Road (APN 506-002-105). he parcel was selected in part because of its location adjacent to the California Department of Fish and Wildlife (CDFW) Mad River Slough Wildlife Area, as well as the City of Arcata’s Marsh and Wildlife Sanctuary. The 38.3-acre Samoa parcel is zoned Agicultural Exclusive within a combining zone for flood hazard and transitional agricultural lands; the parcel is not prime agricultural land. The Samoa parcel has the potential to rehabilitate 36.3 acres of wetland depending on the chosen design.
• Parcel 3 - A third parcel is in the process of being purchased using programmed RW Capital in parent project EA 36600, the Eureka Arcata US 101 Corridor Improvement Project. The 60 acre Diaz parcel (APN 506 021 006) is located west of the City of Arcata,off of Route 255, and is adjacent to the Samoa parcel. The Diaz parcel is critical to the mitigation work as it will allow the restoration of tidal influence. The California Coastal Commission adopted its final findings on parent project, EA 36 600, and provided a consistency determination for the Eureka Arcata US 101 Corridor Improvement Project.

The 2018 increases the funding from $4,190K to $6,079K.

In March 2011, the CTC authorized relinquishment of right of way in the county of Humboldt along Route 255, at Jackson Ranch Road (~ HUM 6.03), consisting of a collateral facility.

Route 255/US 101 Interchange, F Street/Union Street Multi-Modal Improvements (~ 01-Hum-255 8.781/01-Hum-101 85.808)

In March 2026, the CTC adopted the 2026 STIP, which included the following as new programming: PPNO 01-3308, “Rt 255/Rt 101 I/C, F St-Union St Multi-modal improvs” (~ 01-Hum-255 8.781/01-Hum-101 85.808). Programming ($ × 1000): $700 FY26-27 ($700 PA&ED)
(Source: March 2026 CTC Agenda, Agenda Item 4.4; 2026 STIP Staff Recommendations Adopted 2/27/2026)

The "Humboldt Bay Bridge" (unofficial reference) consists of three separate structures: the "Eureka Channel Bridge" (04-0230, HUM 000.20), the "Middle Channel Bridge" (04-0229, HUM 000.67) and the "Samoa Channel Bridge" (04-0228, HUM 001.37). All three structures together were named the "Samoa Bridge" by Senate Concurrent Resolution 52, Chapter 47, in 1971. Individually, the structures have the following additional names:

• Bridge 04-230 (Eureka Channel) is named the "Meyer Bistrin Memorial Bridge". Meyer Bistrin, who emigrated to Oakland, California, in 1926, owned quality clothing stores in Eureka, Arcata, and Garberville and used his civic influence to prevent the building of a freeway through downtown Eureka.. It was named by Assembly Concurrent Resolution 23, Chapter 91, in 1977.
  (Image source: Newspapers.Com: Eureka Humboldt Standard "AM Meyer Bistrin for Council 04.19.65")
• Bridge 04-229 (Middle Channel) is named the "Carl L. Christensen Memorial Bridge", named by Assembly Concurrent Resolution 23, Chapter 91, in 1977. It was built in 1971. Carl L. Christensen, Jr., served the people of Humboldt County in the California State Assembly from 1957 to 1966.
  (Image source: Join California)
• Bridge 04-228 (Samoa Channel) is named the "Richard R. Denbo Memorial Span", named by Assembly Concurrent Resolution 132 in 1980. Richard F. "Dick" Denbo (d. 1980) Manager of the Eureka Chamber of Commerce for 20 years, worked tirelessly for the creation of the Samoa Bridge, a span of which bears his memorial.
  (Image source: Humboldt Area Foundation Donor Yearbook, 2012 | 2013)

• California @ AARoads: California 255
• Gribblenation Blog (Tom Fearer): California State Route 255

Overall statistics for Route 255:

• Total Length (1995): 9 miles
• Average Daily Traffic (1992): 4,600 to 15,800
• Mileage Classification: Rural: 6; Sm. Urban: 3; Urbanized: 0.
• Previous Federal Aid Mileage: FAP: 9 mi.
• Functional Classification: Prin. Arterial: 2 mi; Minor Arterial: 5.5 mi; Collector: 1 mi.
• Counties Traversed: Humboldt.

In 1959, Chapter 1062 defined LRN 255 as “[LRN 235] near Burton to [LRN 107] near Alamo”. This ran from Route 77 near Burton to Route 21 near Alamo. This is not currently part of the state highway system. It was 1963 Route 93 Segment (a), which has since been deleted.

• ⦅Routing⦆
• ⦅Post 1964 Signage History⦆
• ⦅Pre 1964 Signage History⦆
• ⦅Status⦆
• ⦅Named Structures⦆
• ⦅Other WWW Links⦆
• ⦅Statistics⦆
• ⦅Pre-1964 Legislative Route⦆
• ⦅Acronyms and Explanations⦆