Skip to Content
Streetsblog California home
Streetsblog California home
Log In
Streetsblog SF

A Look at Proposed BART Improvements in November 2016 Ballot Measure

Modern signals will mean more capacity. Source: BART
Modern signals will mean more capacity. Source: BART
false

If passed by the BART Board this summer, the November ballot will have a $3 billion-plus bond on it to help BART upgrade its infrastructure, including about $400 million for new train controls and signals. BART's communications staff released some graphics to help voters understand exactly how much additional capacity that will buy, and what that will mean from a rider perspective.

Unlike with an automobile, a train takes a very long time to stop. So the driver of a train can't moderate speed simply by watching the back of the next train without risking a rear-end collision (certainly not if the trains are travelling at speed). Traditionally, railroads work on a block-signal system--trackside signals keep trains a safe distance apart by splitting the right-of-way into segments. A train is not permitted to proceed to the next segment of track until the train in front of it has moved out of it. That assures that trains will never collide. It's what's usually happening when you're on a train that stops between stations for no apparent reason--it means a train in front of it was delayed (often for something as simple as someone holding a door). It causes delays to ripple back--so a single delayed train can cause problems way down the line. It also limits capacity.

Here's another way of looking at it, from a BART statement:

The current train control system is called a track circuit-based system with hard wired electronics. In its day, it was cutting edge. It divides BART’s entire 104 miles of track into smaller fixed segments, or “blocks.” Imagine a series of hotel rooms with adjoining doors. A train is not allowed to use an adjoining door to enter a room until a train in that room has exited through the other adjoining door.

This “go, no-go” movement is managed digitally through a system that’s based on the track circuit. The train control fixed blocks are just like the hotel rooms – you can’t move the walls.

But a modern computer, with the proper signal electronics, can run more trains closer together, always keeping a safe distance so one train will never be close enough that it can't stop before hitting the next. In other words, with modern signals and controls, you can move the walls of the hotel rooms, surrounding each train with an electronic safety "bubble" that will slow a train if it starts getting too close to the one in front of it. Under this system, trains rarely stop in-between stations unless there's a serious breakdown.

So how much delay time on BART is attributed to its aged signals and controls? Here it is BART's words:

NUMBER ONE CAUSE OF DELAYS: Currently, more than half of BART’s infrastructure related delays are due to the train control system, causing BART riders to face more than 400 hours of delay each year.

The new system will also be just plain safer:

"Train control is safety-critical," said Tom Dunscombe, BART's Group Manager of Train Control Modernization. "Train control will slow down and safely stop the trains as required for normal operations or in the event of an equipment failure.”

The second BART graphic helps illustrate how modern train systems work.

If computers know exactly where the trains are at all times, they can run closer together--and capacity goes way up. Source: BART
If computers know exactly where the trains are at all times, they can run closer together--and capacity goes way up. Source: BART
false

Of course, this is only one improvement BART is hoping to make. It'll also be replacing rails, power distribution, and, of course, the cars themselves.

The San Francisco Bay Area Planning and Urban Research Association (SPUR) is also getting the message out, at the same time fighting for more ambitious improvements, such as a second Transbay tube. And tonight, BART Board Member Nick Josefowitz will talk more about what needs done at the San Francisco Bicycle Coalition offices, starting at 5:30 pm.

Stay in touch

Sign up for our free newsletter

More from Streetsblog California

Covina to Begin Construction on Recreation Village

The new facility will be next to the Metrolink station and include a variety of opportunities for fitness and amusement

July 26, 2024

Talking Headways Podcast: Have Cities Run Out of Land?

Chris Redfearn of USC and Anthony Orlando of Cal Poly Pomona on why "pro-business" Texas housing markets are catching up to "pro-regulation" California and what it might mean for future city growth.

July 26, 2024

Friday’s Headlines

Oakland identifies sites for speed camera pilot; E-bike tariffs conflict with US climate policy; Pollution spikes around warehouses, shipping hubs; More

July 26, 2024

What the Heck is Going on with the State E-bike Incentive Program?

The program's launch has been delayed for two years, and currently "there is no specific timeline" for it. Plus the administrator, Pedal Ahead, is getting dragged, but details are vague

July 26, 2024

The Paris Plan for Olympic Traffic? Build More Bike Lanes

A push to make Paris fully bikable for the Olympics is already paying dividends long before the opening ceremonies.

July 25, 2024
See all posts