The City of San Francisco has published a complete application notice for the plans to redevelop the 4th and King Station into a master-planned neighborhood in SoMa, San Francisco. The notice establishes a deadline for the planning department to make a final decision by mid-June. Prologis is sponsoring the development, in partnership with Caltrain.
Caltrain San Francisco Railyards high-commercial variant, illustration by Prologis
Caltrain San Francisco Railyards high-residential variant, illustration by Prologis
The developer is expecting to construct between 7 and 8 million square feet at full build-out, including approximately 4 million square feet of commercial office space and roughly 2,500 dwelling units. The tallest tower would rise around 850 feet above 4th and King Street, with the new Caltrain Station at its base. The first phase of construction includes 2.5 million square feet on the blocks at 4th Street and 7th Street.
The application writes that the “Proposed Project would modernize the Caltrain Station and Railyard, in coordination with the Transbay Joint Powers Authority’s construction of the Portal Project and the Pennsylvania Avenue extension.” The Portal is the proposed extension of Caltrain to the underground platform station below the Salesforce Transit Center, next to the Salesforce Tower.
Caltrain San Francisco Railyards sidewalk view of the new Train Station, rendering by Prologis
Caltrain San Francisco Railyards internal view, rendering by Prologis
At the core of the project’s pitch to the city, Prologis is promising to build a world-class transit hub, a major new mixed-use development, and provide grand public spaces while reconnecting the urban grid. The importance of the redevelopment is in part because the site is expected to serve as the city’s gateway to the California High-Speed Rail network.
Prologis is a San Francisco-based real estate company specializing in logistics facilities and warehouses worldwide. The international firm appears very capable at planning the infrastructure for the rail network to run through or below a mixed-use neighborhood. Given its previous work and the complexity of the proposal, Prologis may consider partnering with an experienced real estate developer to achieve the overall vision.
Caltrain San Francisco Railyards proposed site plan, illustration by Prologis
Caltrain San Francisco Railyards view of Station Lane, illustration by Prologis
Caltrain San Francisco Railyards front view of the new station entrance, rendering by Prologis
Plans to form a joint venture or find a co-sponsor have not been announced. An example of a potential partner with relevant experience in the Bay Area is Related Companies. Over in New York City, Related Companies and Oxford Properties are co-developing the 28-acre Long Island Rail Road’s storage yard into Hudson Yards, a mixed-use high-density neighborhood costing an estimated $25 billion.
The western end of the trainyard plan is across from the former Recology center at 900 7th Street in the Showplace Square. In 2019, Recology filed plans to reshape the 5.8-acre block with 1.25 million square feet of development, including several hundred housing units, offices, and light industrial space. Then, in late 2020, the property was sold to Amazon, and the tech giant filed plans for a new distribution center. Plans for the warehouse are still under review and awaiting approval.
Caltrain San Francisco Railyards view of the 5th Street Park, illustration by Prologis
Caltrain San Francisco Railyards site area context, illustration by Prologis
A significant question posed by the developer is whether to have the train tracks at-grade or below ground. The construction schedule estimates that a below-grade rail iteration could take around 13 years to complete, or 12 years for the at-grade rail version. The estimated cost has not yet been shared.
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This kind of redevelopment around Caltrain’s 4th & King station highlights a bigger issue with San Francisco’s transportation priorities.
Transit-oriented projects assume ridership will keep growing, but in reality, usage has been uneven and recovery has been slow and inconsistent. At the same time, a large share of residents, commuters, and visitors still rely on cars—and that demand isn’t going away.
Yet the city continues to underinvest in basic driving infrastructure. Anyone who spends time in SoMa knows how limited and unreliable parking is, especially for visitors, service workers, and people with mobility challenges. That has real impacts on accessibility and local business activity.
A more balanced approach would acknowledge both realities: continue improving transit, but also invest in practical needs like secure parking garages, better-managed street parking, and road infrastructure that reflects current demand.
If this project is meant to serve the broader public, it shouldn’t be built on the assumption that everyone will shift to transit. Planning should reflect how people actually move through the city today—not just long-term goals.
Where are you getting your data that ridership is soft for Caltrain? I see the contrary.
Further, it does not make sense in this spot to double down on investing so much money and space for cars to sit around when you’re literally on top of a train station and there’s other modes of getting around in that area. And if you want traffic and parking to be easier, you don’t incentivise car use and subsidize people owning cars.
Similar to so many other projects in the city, no one who absolutely needs a car is being forced to live there. I trust that if that’s someone’s situation, they would make better housing choices.
Frankly, building more car infrastructure like parking garages and wider streets is ugly as hell. And comes at a cost in this case of fewer homes/commercial spaces and/or more expensive homes/commercial spaces to offset the fact that you won’t recoup the money spent on car infrastructure.
bro what
Anti-transit rants can’t change the laws of physics. Cars take up space. The bridge ain’t getting bigger. 101 ain’t getting bigger. It’s wild to respond to a great transit-oriented project with “Nah, I love traffic and paying for parking.”
When office attendance finally rebounds — which it has in other cities like New York — transit ridership will as well.
SF spends hundreds of millions on streets every year.
Bruh, have you not ridden Caltrain lately? It’s standing room only in the mornings going south toward SJ and the same coming back to The City in the evenings. The last thing we need to do is make it easier for motorists. SOMA is a lawless free-for-all as it is, with drivers squishing pedestrians daily.
Are you high? We literally spend orders of magnitude more on car infrastructure than transit.
Ahh, look up the definition of “induced demand”, my dude. The last thing we need on top of 2 literal train stations is a massive parking garage. Perhaps you’d be better suited to live in LA or Texas?
Bruhhh nobody reading all that. It’s pretty simple: Cars are a massive drain on city finances and people are finally waking up to the reality that cars are a drain on their personal finances. The invisible hand of economics speaks once again. The end.
I can totally get behind a project like this. What a way to repurpose inner-city brownfield sites. It reminds me a lot of the Mission Rock project, which is turning out nicely.
However, I am curious about how Caltrain would work with this….assuming that Caltrain eventually gets to the Transbay Terminal, what happens to the actual railyard/maintenance facility? Presumably, that ain’t getting put in the basement of this project? And Caltrain can’t use the old SP railyard in Vis Valley, ’cause that’s theoretically going to be redeveloped some day. Where does the rail yard go? Curious minds what to know.
The replacement passenger platforms will be shifted off to the side under Townsend, and there will be fewer of them because 4th & King will no longer be a terminus station. It is possible that the yard simply gets moved underground in the existing footprint, similar to the way the Hudson Yards development was built over tracks in Manhattan. It’s also been suggested that a yard be built for CAHSR (which I’m sure could be designed to accommodate Caltrain as well) at the south end of the Baylands area in Brisbane, beyond the planned Schlage Lock and Baylands development area.
Thanks for the info. Anonymous. Yes, I was wondering about this. I figured the new station would be smaller since it would no longer be the terminus. I suppose now that Caltrain is electric, no need to worry about diesel pollution and dirt filtering up from the yard beneath the development, but seems like it could be kind of loud/shaky. Putting the Caltrain/CAHSR rail yard in the Baylands area, which is where the SP yard was once located, makes a lot of sense, but I was under the impression that that entire area was earmarked for development. Of course, nothing has come of it for decades.
The Brisbane Baylands Specific Plan is under active review by City of Brisbane right now. The revised plan includes the CHSR yard
I don’t agree with this direction at all. San Francisco keeps doubling down on transit-first planning while ignoring the fact that a huge number of people still rely on driving every day.
You can argue theory all you want, but the reality on the ground is congestion, lack of parking, and limited accessibility for anyone who isn’t perfectly served by systems like Caltrain or BART.
Not everyone can or wants to take transit, and not every trip makes sense on transit. Designing the city as if cars are the problem instead of part of the transportation mix just creates more friction for residents, workers, and visitors.
I’m not buying the idea that making driving harder somehow fixes everything. It just shifts the burden onto people who don’t have good alternatives.
It’s literally how every age-ed, densely populated on Earth works. Driving is not an efficient or effective way to move people around shorter distances, so invest in mass-transit to get as many people out of their single-use, circle-the-block, take-up-space, cars. Cities with fewer people circling the block are cleaner, quieter, healthier, happier and… drum roll… cheaper to live in.
Short distances OR long distinaces.
Yes, thank you.
“Driving is not an efficient or effective way to move people around shorter distances…”
Really? Please tell us about the last time you took the train to the supermarket and then back, weekly, for your 5 person family’s grocery needs.
If you think a weekly big trip to the supermarket should be part of your routine in a dense, walkable neighborhood then you’re just plain doing it wrong.
San Francisco, Chicago, New York, Boston, and a few other places are literally the only places in this country where you can live without using a car for nearly every journey. Hell, the rest of the country you can drive, drive, drive, and park, park, park to your heart’s content. Can we not have one place where we can live not a slave to our automobiles? Plus, the planet is burning up bruh.
This plan doesn’t remove any existing parking or contract any roads (it even adds some connector roads). So even if we take your delusions at face value, you’re still wrong.
Thank you for pointing this out, this article doesn’t even say it won’t include parking garages, in fact I bet there will be at least one parking spot for every unit built.
So basically your position is “Even with the 275,500+ [free] parking spaces and countless paid lots threaded throughout the entire city, don’t build transit-oriented housing or mass-transit because we need more free parking as a result of too many people driving.” 🤔
Very informative. Thank you. I was attracted by the article’s title: “Approval deadline…” and wonder if I missed the date in the article. What is the date of the approval deadline?
Considering below grade adds a year but cuts down on the noise from the trains and visual clutter and the dust generated by above ground trains it seems like a project that is costing this much money to build, it is more than worth the added time and expense of burying the tracks and not having what would be a big scar running through the neighborhood landlocking things. Nobody wants to hear the sounds of trains all day and night, or wants to see a view of train tracks and all the overhead lines. Yes a distant train whistle off in the distance heard between cricket chirps and cicadas and other critters that make noise at night seems like a romantic throwback from another time, but the people who think that are not the people who live right next to the tracks. SF needs more housing that people who don’t make 150k a year can afford without 3 roommates, this is a chance to remedy that with the more residential version of the plan, realistically I think make the towers mixed use, bottoms retail at street level parking then commercial for bottom 3rd-half of the building and residential the top half. With new build, plumbing lines can be run under each floor slabs preemptively for the commercial floors so if it turns out the office space is not filling up, it is easy to complete the tie in to the plumbing and sewer stacks that serve the rest of the building turn some of those vacant office floors into more residential, whether it be more apartments, condos or hotel rooms. Too much office space creates a bit of a dead zone in the evening hours, this would make it so there is enough foot traffic to support the restaurants and retailers and nightlight spots in the neighborhood instead it being another city neighborhood that is a ghost town after the office workers go home as is the case with most city neighborhoods with more office than residential space.
20 more years without a train at Transbay
A few replies are arguing against things I didn’t actually say. I never said anything about free parking, unlimited parking, or replacing transit with cars.
My point is simpler: even in a dense city like San Francisco, cars are still a necessary part of how people actually get around—whether it’s for work, mobility needs, deliveries, or trips transit doesn’t fully cover.
And on the parking point—yes, there is parking in the city, but that doesn’t mean it works well in practice. It can be scarce, inconsistent, and difficult to access, especially in high-demand areas like SoMa. Availability, cost, and location all matter, particularly for visitors, service workers, and people with mobility challenges.
I also don’t see anything in the article that clearly explains how parking or car access is being handled. Some comments are assuming it’s covered, but that’s not actually addressed—and those details matter if we’re talking about how the area will function day to day. That’s why it’s important to raise these questions early so they can be planned for.
I understand the space constraints, but that doesn’t mean car demand disappears. It just means it needs to be managed and planned for in advance in a realistic way.
That’s why it’s smarter to plan for both—transit and driving—because a system that accounts for both tends to be more reliable, more accessible, and works better for more people in practice, not just in theory.
The point is that the best way to improve traffic and parking scarcity is to increase public transit and build near transit. Building more car infrastructure only exacerbates these issues in the surrounding areas.
There will undoubtedly be parking minimums mandated for these developments. While parking is necessary, historically these mandates have tended to be far too high when one accounts for the negative impacts on the surrounding communities. So I am personappy not worried about them being too low.
You’re right, the car won’t disappear entirely but it can very easily be deprioritized, and discouraged in order to curb “demand”. That’s the strategy you think is missing. It’s right there in front; reduce the convenience for driving to encourage people to rely more on transit or—in some utopian version of the future—get rid of their car, save money, take the scenic route and enjoy living in such an accessible, walkable, dynamic city.
It’s amazing that you can’t see how the traffic and parking problems are caused by people in cars and not the lack of planning or by TOD.
@David
If people need parking somebody will open a garage. This project is literally on top of rail. We’ll be ok
Solved
A swing in a miss — leaving those gigantic freeway viaducts in place shows a lack of foresight on this project. Demolishing those would open up space, restore views, and provide ample opportunity for new development — not to mention decreasing traffic violence in an area with so much reckless driving.