California Highways (www.cahighways.org): Route 150

In 1934, Route 150 was signed along the route from Surf to Jct. Route 126 at Santa Paula, via Santa Barbara and Ojai. It consisted of the following segments:

Present-day Route 246 between Surf and Santa Ynez. This was LRN 149, defined in 1933. Although originally part of Route 150, in 1961 it was resigned as Route 154. It was resigned as Route 246 in 1964.
Present-day Route 154 between Santa Ynez (LRN 149) and Santa Barbara (US 101, LRN 2). It is unclear if the portion between LRN 149 and LRN 2 (US 101) near Zaca (near Los Olivos) was also signed as Route 150. This was LRN 80, also defined in 1931. Certain sections of old Route 150 are covered by Lake Cachuma. The old bridge crossing the Santa Ynez River is still there serving as a cow crossing. A section of Route 150 runs off of Route 154 and heads up to Bradbury Dam. There it disappears underneath the dam and heads up the middle of Cachuma Lake. Stagecoach Road is the old Route 150 from the days before the large bridge across Cold Springs Canyon. It was created as a state highway to provide relief for LRN 2 (US 101). By creating it, the state hoped that it would indefinitely postpone radical widening of the present state highway through Gaviota Canyon and along the coast, which would destroy valuable landscape and property.
Present-day Route 192 between Route 154 and present-day Route 150. This is LRN 80, defined in 1933.
Present-day Route 150 between Route 192 and Route 126, passing through Ojai. This was LRN 151, defined in 1933.

The route was opened in 1897. Before the construction of US 101, it was part of the main highway between Los Angeles and Santa Barbara.

At some point between 1936 and 1938 a small segment of State Highway was added that aligns with present Route 154 on San Marcos Pass Road between US 101 and Route 192. It appears this segment of highway was a spur of LRN 80 (according to the 1959 definition) and can be seen appearing by comparing the Santa Barbara Area on the 1936-37 State Highway Map to the 1938 Edition. This small portion of highway is important since it appears to have ultimately been the driving force for Route 150 breaking into several highways. Beginning in 1950 construction of Bradbury Dam in Santa Barbara on the Santa Ynez River began and was completed by 1953. This required that much of Route 150 between Santa Ynez and Devaul Canyon be relocated uphill to the south of future site of Lake Cachuma. Presently this alignment is still in use as San Marcos Pass Road on Route 154.
(Source: Gribblenation, "California State Route 150 family of highways (CA 246, CA 154, CA 192 and CA 150)", visited on 11/9/2019)

In 1961,CA 154 was first signed between Surf and US 101 in Santa Barbara. This resulted in Route 150 being truncated to Route 154 just short of San Marcos Pass in Santa Barbra. This change can be observed by comparing the 1961 State Highway Map to the 1962 Edition.
(Source: Gribblenation, "California State Route 150 family of highways (CA 246, CA 154, CA 192 and CA 150)", visited on 11/9/2019)

When construction of Castias Dam on the Ventura River of Ventura County began in 1956 the original alignment of Route 150 had to be relocated. The Castias Dam project shifted the alignment of Route 150 from the east bank of Santa Ana Creek to the west bank. The alignment of CA 150 west of Santa Ana Creek is still part of the modern highway on Castias Pass Road. Castias Dam was completed by 1959 and the original alignment of Route 150 can be seen south of the Marina Cafe when Lake Castias is low.
(Source: Gribblenation, "California State Route 150 family of highways (CA 246, CA 154, CA 192 and CA 150)", visited on 11/9/2019)

Sign Route 150 appears to have been an interesting hydra in the area, meaning that there were multiple roads signed as Sign Route 150. The main route—that is, the one that appears to correspond with the state highway map—entered from the Santa Barbara area along Casitas Pass Road. As it neared the lake approaching from the W, it made a horseshoe turn and proceeded to cross the lake along a route that is now underwater, veering N to meet Baldwin Road near the SB Santa Ana Road connection. Sign Route 150 then followed Baldwin Road (and Old Baldwin Road) to meet Ventura Avenue. But the USGS maps also show other routes signed as part of Sign Route 150: Notably, a connection (again, now underwater) to Casitas Vista Road that continued to meet Ventura Road, where it continued S into Ventura as a US 399/Sign Route 150 cosign. Sign Route 150 split off to the W at Casitas Vista Road (nee Casitas Pass Road); however, that route was later obviated by the filling of Lake Casitas. The pre-lake Sign Route 150 met another road that is now also underwater, continuing to the NE to about where Santa Ana Road is. where it met today's Route 150 at Baldwin Road. That same USGS map also shows Sign Route 150 running from the Ventura Road/Santa Ana Road junction along Santa Ana Road and Burnham Road to Baldwin Road. However, it is clear that Sign Route 150 shared US 399 between Baldwin Road and Ojai Avenue, split back off on its lonesome to the E along Ojai Avenue as solely Sign Route 150.

In August 2011, the CTC approved $753,000 in SHOPP funding for repairs near Santa Paula, at Reeves Road (~ VEN 19.931) and at Rafferty ~~Ranch~~ Road (~ VEN 30.989), that will restore 8.5 acres of riparian and upland habitat as required on and off site mitigation for environmental impacts on previous emergency projects at two locations. (FCO)

Santa Paula Creek Bridge № 52-0105 Replacement (07-Ven-150 28.610)

In June 2026, the CTC amended the following project into the 2026 SHOPP: 07-Ven-150 28.610. PPNO 07-6275; ProjID 0724000157; EA 50150. Route 150 Near Santa Paula, at Santa Paula Creek Bridge № 52-0105. Replace bridge, reconstruct fish passage system and restore creek bed. Concurrent COS allocation under Resolution FP-25-106; June 2026. Future SB 1 Baseline Agreement required. Allocation ($ × $1000): PA&ED $3,125; PS&E $4,939; R/W Sup $502; ⊘Con Sup $10,676; ⊘R/W Cap $6,423; ⊘Const Cap $38,266; TOTAL $63,931. BC: 12/5/2031. ⊘” indicates phase not authorized.
(Source: June 2026 CTC Agenda, Agenda Item 2.1a.(1a) #28)

In June 2026, the CTC approved the following allocation for SHOPP preconstruction project phases (environmental support, design, and R/W support): $3,125,000. 07-Ven-150 28.610. PPNO 07-6275; ProjID 0724000157; EA 50150. Route 150 Near Santa Paula, at Santa Paula Creek Bridge № 52-0105. Replace bridge, reconstruct fish passage system and restore creek bed. Concurrent Amendment under SHOPP Amendment 26H-002; June 2026. Pre-Construction Phase Allocation ($ × $1000): Budgeted (Actual, if different): PA&ED $3,125.
(Source: June 2026 CTC Agenda, Agenda Item 2.5b.(2a) #17)

In March 2024, it was reported that a massive mudslide has blocked off a stretch of Route 150 north of Santa Paula, closing the road between Santa Paula and Ojai (from Steckel Park (~ VEN 30.299) to Stonegate Road (~ VEN 32.032)). According to Caltrans, the hillside along Route 150, also known as Ojai Road, began to slide in early February 2024, as massive storms rolled through the area. Now, more than 150 feet of the road is completely covered by mud and debris. The suggested detour leads drivers nearly 40 miles out of the way, through the cities of Ventura and Ojai using Route 126, US 101, and Route 33. Caltrans says it hopes to have one lane of this section of Route 150 open by the end of May.
(Source: Fox 11, 3/2/2024)