State Route 94 (SR 94) is a state highway in the U.S. state of California that is long. The western portion, known as the Martin Luther King Jr. Freeway, begins at Interstate 5 (I-5) in downtown San Diego and continues to the end of the freeway portion past SR 125 in Spring Valley. The non-freeway segment of SR 94 that continues east through the mountains to I-8 near Boulevard is known as Campo Road.

The Campo road served as a wagon road providing access to eastern San Diego County as well as Imperial County. The road was added to the state highway system in 1933, and signs for Route 94 were posted along local roads later that decade. Efforts to convert the western half of the route to a freeway got underway in the 1950s, and the freeway was complete by 1962 west of the road that became SR 125. Construction continued east to Avocado Road over the next few years. Various proposals for widening the highway have come from the California Department of Transportation (Caltrans), but local opposition resulted in the delay or cancellation of many of these proposals.

Route description Route 94 is defined in section 394 of the California Streets and Highways Code, and that the highway is "from Route 5 near San Diego to Route 8 west of Jacumba via Campo".

SR 94 is an east–west freeway that begins at the eastern end of the one-way couplet of F and G streets in southeast San Diego. The freeway continues through an interchange with I-5 just east of downtown. Following this, the route goes through the neighborhoods of Sherman Heights, Grant Hill, Stockton, and Mount Hope, where there is an interchange with SR 15. Shortly thereafter, SR 94 intersects I-805 in Chollas View before continuing east through Emerald Hills and Chollas Creek into the city of Lemon Grove. Passing by the Marketplace at the Grove shopping center, the freeway forms the boundary between Lemon Grove to the south and La Mesa to the north, up to the SR 125 interchange where SR 94 turns east. At this point, SR 94 leaves both cities and enters unincorporated Spring Valley and Casa de Oro.

The freeway becomes an undivided highway at Via Mercado in Rancho San Diego. SR 94 continues through Rancho San Diego by turning southeast at the Jamacha Road and Campo Road intersection, where SR 54 and CR S17 turn northeast. As Campo Road, SR 94 crosses the Sweetwater River before entering a less-developed area, winding through the communities of Jamul, Dulzura and intersecting the north end of SR 188 north of Tecate. After passing through the communities of Potrero, Campo, and the Campo Indian Reservation, SR 94 continues east onto old U.S. Route 80 (US 80) briefly before turning north on Ribbonwood Road west of Boulevard. The route ends by connecting to I-8 near Manzanita.

SR 94 is part of the California Freeway and Expressway System; west of SR 188, it is part of the National Highway System, a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration. SR 94 is eligible for the State Scenic Highway System, but it is not officially designated as a scenic highway by the California Department of Transportation. In 2014, SR 94 had an annual average daily traffic (AADT) of 440 vehicles at Live Oak Springs Road, and 179,000 vehicles between I-805 and 47th Street, the latter of which was the highest AADT for the highway.

History

Campo Road SR 94 was built along the routing of an old stagecoach road that was part of the primary road from San Diego to Yuma, Arizona. A trip to East County in the 19th century along the road would last two days. James Pascoe surveyed the route through Campo for the county in 1869 that was shorter than the existing route through Warner's Pass. The road was known for its curves, climbs, and boulders, making travel difficult. The first automobile went on the road in 1904. By 1913, an unpaved automobile road extended to Campo from San Diego, and work took place to improve the condition of the road in 1916. A year later, the road continued east to join with the state highway leading into Imperial County. In 1927, the Potrero bridge was replaced, after a storm washed it out. By 1928, the paving of the Campo road was about 43 percent complete. In February of the next year, the progress was at 74 percent; the total cost was $122,474 (about $ in dollars). The Sweetwater bridge was finished in March at a cost of $60,000 (about $ in dollars). The Campo road was the only road through the Peninsular Ranges to stay open for the entirety of the next winter; other roads were closed by snow, leading to increased traffic along this road. This was largely due to the lower elevation of the road, at only .

Designation and initial construction

In 1931, the County Board of Supervisors agreed to submit the Campo road for consideration as a secondary state highway. The state considered the inclusion of the Campo road into the system in 1932. The California State Legislature defined Route 200 in 1933 as a route from San Diego to west of Jacumba, going through the town of Campo. The San Diego Chamber of Commerce sent a representative to ask the state for funding for paving the Campo highway in 1935, and the road was paved that year. The Chamber also asked for the war department to declare the road a military highway to receive federal assistance for its improvement. Signs were posted for SR 94 in 1937, and by 1938, SR 94 was signed along Broadway and Lemon Grove Boulevard (later Federal Boulevard) before continuing east to Campo.

The next year, the California Highway Commission declined to have the Campo road improved. However, the Highway 94 association, as well as the Campo-Potrero and Highway 80 chambers of commerce raised concerns about the safety of the children going to school in the buses along the road. In 1952, the Southern California committee of the state Chamber of Commerce recommended to the California Highway Commission that Route 94 be widened to four lanes from the Wabash Freeway to Jamacha. In June 1953, the Commission approved an eight-lane freeway for Route 94 from Home Avenue in San Diego to Palm Avenue around La Mesa. The local Board of Education also gave their approval, which was required because the freeway would be built on land that was for a proposed school. But the next month, State Senator Fred Kraft criticized the proposal because he believed that it would be too expensive and would not reduce congestion in the long term. Approval extended to the junction with US 80 by October 1953; the part from 18th Street to Wabash Boulevard followed in November 1954. Later that year, a toll road that would have tunneled under the Laguna Mountains and bypassed Route 94 was proposed by the county Board of Supervisors. The state allocated $3.48 million (about $ in dollars) for making SR 94 a freeway from College Avenue to Campo Road in October 1954.

Construction began on the first part of the SR 94 freeway just west of Lemon Grove by May 1955. The contract for the College Avenue to Campo Road portion was given out in October, for $2.9 million (about $ in dollars). Preparation for bidding on the portion from the Wabash Freeway to near Euclid Avenue took place towards the end of the year; construction was underway by May 1956, as was planning for the portion west of there to the intersection of 18th and F streets and the future interchange with US 101 (Now I-5). The San Diego City Council requested that an overpass be constructed at 22nd Street to provide improved access; an underpass for the road was eventually built. The freeway from Wabash Boulevard and 56th was completed on March 18, 1957; metal-weakened plane joints were used for the construction, which the California Division of Highways considered "experimental" at the time. East of College Avenue, some unwanted cracks developed in the roadway during the joint pouring process, and were repaired with epoxy. At one point in 1958, SR 94 was considered as a possible extension of US 90, a route proposed to run along the southern border of the United States to Florida, by the South Bay Highway Association. By August, SR 94 from Palm Avenue to Jamacha was being planned.

The western end of SR 94 connecting to US 101 was put up for the bidding process in late 1958. Construction on the interchange with US 101 began in 1961. By January 1962, the freeway was mostly complete west of La Mesa and the freeway connection to US 80. The part of the freeway from 25th to 17th streets was completed in November. In the 1964 state highway renumbering, SR 94 was officially designated from I-5 to I-8 near Jacumba, and SR 125 was designated from SR 94 near La Mesa north to SR 56.

Expansion and naming Land acquisition for the construction of the SR 94 freeway through Spring Valley had begun by 1965. The next year, a plan to reroute and widen portions of SR 94 from the Sweetwater River to I-8 was underway, with a Caltrans proposal to remove the "Frenchy's" or "Three Springs" curve. In March 1968, the San Diego Highway Development Association considered the construction of the freeway from SR 125 to Jamacha Junction a priority. The state announced in August that the Spring Valley widening project would be funded earlier than anticipated, because of the state of the economy. Meanwhile, a $1.8 million (about $ in dollars) contract to widen SR 94 to eight lanes from Wabash Boulevard to Waite Drive in Lemon Grove was awarded in October. The freeway from Kenwood Drive to Avocado Boulevard in Spring Valley was completed in July 1970.

An improved interchange with SR 125 was being planned in 1974, which would connect to the existing freeway extending to Avocado Boulevard. Construction began in October, and continued into late 1975, at a cost of $11 million (about $ in dollars); the road was predicted to reduce traffic at the intersection of Campo Road and Bancroft Drive, and interchanges at Spring Street and Lemon Grove Avenue were to be built. The Lemon Grove Avenue interchange was open by January 30, 1976, and parts of the interchange with Spring Street and SR 125 was open by July 20.

By 1977, much of the SR 94 freeway was congested, with 85,000 to 95,000 trips per day on the freeway according to Caltrans. It was hoped that the construction of SR 54 to the south and SR 125 would reduce traffic by 20,000 trips per day. Onramp meters were installed in 1978 to throttle traffic entering the freeway with a centralized computer system; this resulted in reduced congestion on the freeway, according to motorists. In 1987, the bridge over the Sweetwater River that had been used for 58 years was replaced by a new bridge, at a cost of $2.3 million (about $ in dollars); construction had been delayed by nine months by concern over environmental harm to the least Bell's vireo.

The highway was designated the Martin Luther King Jr. Freeway by the California State Legislature in September 1989, after a two-year struggle to find a suitable tribute to King in the San Diego area. Nevertheless, the measure did not include funding for the signs, and as a result, they were not installed until 1998, when they were funded by the San Diego Association of Governments with $1.4 million (about $ in dollars) from a local sales tax.