Description
In 1925, the Los Angeles city council hired financial consultant firm Kelker, De Leuw & co. to investigate the potential need for a rapid transit system to more efficiently link the growing suburbs to downtown. The firm drew up a proposal for a system that would run in three subways through downtown, two of them north-south cut and cover lines (running along Olive St and Broadway) and the third a deeper east-west line along 7th Street. These three lines would then run out into the suburbs through a network of branch lines, some of them elevated and some of them running on trackbeds, initially connecting Highland Park, Hollywood, Lankershim (what is today known as North Hollywood), Vineyard Junction, Wilshire (Koreatown today), Mid-Wilshire, the South Central, and the Eastside. However, due to the large number of elevated lines that would be built on thoroughfares (most notably Sunset Boulevard and Pico St), the business community vehemently opposed the plan, and along with fears of wealth desegregation and an unwillingness by voters to fund the private railroads with tax money, the nascent subway system was never funded.
Imagine, however, that the local heavy construction firms had gotten wind of the plans, and been convinced of the good such a project could do to the city in general and the construction business in particular. Given their undying support for freeway expansion and similar public works projects IOTL, it wouldn't be hard to see them push for a subway and create a larger support base for the plan. Though it's still unlikely for it to be adopted in the political climate of the time, there would probably follow a broad public debate over the plan, and rather than disappearing into obscurity the plan would leave a clear mark on the city.
Come the Depression and FDR's New Deal programs, which funded extensive transit construction in other cities (notably the Independent Subway System in New York, as well as the State Street and Dearborn-Milwaukee subways in Chicago), we could potentially see the plan being adopted, given federal funding, and have at least one of the lines open by the outbreak of World War II. With a rapid transit system in what is arguably the cultural capital of America (at the very least of the West), perhaps the "car culture" of the 1950s and 1960s would be less pervasive, and the attitude toward public works in general a more positive one. I would imagine that construction would still slow down throughout this period, simply because the freeways and suburban housing developments would take large amounts of government money away from the subway system.
However, with a smaller part of its lines running at-grade, the Pacific Electric would perhaps remain in existence for decades longer than OTL, and if so it would slowly upgrade its interurban lines to full metro standard, in accordance with the plan's suggestions. It would, however, still fall under government control eventually, and be integrated into the existing subway system. These upgrades, along with extensions of the city subway to the outer suburbs, places like Redondo Beach and San Fernando, would stand to benefit from the oil crisis of the 1970s (assuming that it happens as per OTL) and the surge in both public approval and federal funding for transit that came with it.
By the turn of the millennium, the plans laid out in 1925 would likely be completed, and even with a few extensions added. This is the situation that my map represents, although it's worth mentioning that this isn't the exact plan as it was laid out - the lines to LAX and Santa Ana are my inventions (the plan only included Los Angeles County, and there weren't enough airline passengers at the time to justify an airport extension, nor had LAX been built at the time), and the report said absolutely nothing about stop locations.