State Route 152 (SR 152) is a state highway that runs from east to west near the middle of the U.S. state of California from State Route 1 in Watsonville to State Route 99 southeast of Merced. Its western portion (which is also known as Pacheco Pass Road and Pacheco Pass Highway) provides access to and from Interstate 5 toward Southern California for motorists in or near Gilroy and San Jose. Route description Route 152 begins near Route 1 as a series of local streets that run through downtown Watsonville: East Lake Avenue carries it to the intersection of Casserly Road. This point marks the start of a winding two-lane highway that crosses the Santa Cruz Mountains through Hecker Pass to reach Gilroy. In Gilroy, it is again carried on a series of local streets, then overlapped onto U.S. Route 101 for a small stretch before it separates again a short distance to the south and returns to heading east/west on more local streets in Gilroy. After exiting the large commercial developments near U.S. 101, Route 152 consists of a single lane in each direction, with narrow shoulders, rain ditches on either side of the road, no center dividers, and posted speed limit of 55 mph (89 km/h), making it prone to head-on collisions. Headlights are required at all times along this portion. This segment is a significant bottleneck for traffic traveling along Route 152 between the San Francisco Bay area and the Central Valley. Upon reaching Route 156 near Hollister, the road expands to two lanes in each direction, and climbs and curves along the valley of Pacheco Creek into the mountains of the Diablo Range, crossing them through the Pacheco Pass into the San Joaquin Valley. SR 152 is one of the three major routes that cross the Diablo Range after Interstate 580 and State Route 46. Pacheco Pass is higher than Altamont Pass to the north, but lower than Polonio Pass to the south. Route 152 continues as a four-lane divided expressway, descending along the northern and eastern shore of the massive San Luis Reservoir. The route passes in between the San Luis Dam and the O'Neill Forebay. The route continues east and passes a large Path 15 substation and then meets Interstate 5 as an expressway. It becomes a speed-limited city street, Pacheco Blvd., while passing through Los Banos. It then returns to an expressway until