07 January 2024

New Year, New Risks

It's 2024, the year that Caltrain is supposed to go electric. All the wires are up and six trains are already on the property (see delivery spreadsheet), with more on the way shortly. After years of delays, will they pull it off?

Seems like a good time to review five risks facing the project.

1. PCEP schedule slips - while monthly reports of the Peninsula Corridor Electrification Project continue to assert that the project is on track for "Fall 2024," a nebulous date that could well be the last day of fall or December 20th, there are worrying slips in the project schedule. The November 2023 monthly report (from the January board meeting packet, PDF page 131) revealed a three-month slip in the critical path compared to the previous monthly report (from the December board meeting packet, PDF page 159). Completion of live runs on segments 1 and 2 between San Francisco and Menlo Park was pushed out from 12/17/2023 to 3/16/2024. Three-month slips this close to the finish line do not bode well for finishing on time.

Tree down on wires (KRON4)
2. Trees falling on tracks - as reliably as atmospheric river storms occur in the Bay Area, large trees will continue to fall across the tracks. Previously, a few hours of chainsawing was enough to clear the blockage and resume service. No longer: trees will now damage the overhead contact system (OCS), requiring repairs to high voltage equipment before service can resume. On January 5th, 2023, a large eucalyptus tree fell across the tracks and did just that. According to a news report, service was interrupted for most of the day to safely remove mangled poles and wires-- and this without any urgency to repair them before restoring diesel service.
Another one, February 2024

The craziest part of this story: it took until September 2023, a gestation period of nine months, to complete the OCS repairs due to long lead times to procure replacement parts. While there would have been more urgency had the OCS been needed to operate the service, this episode highlights a lack of preparedness for what will become a routine occurrence. It should not take more than a few hours to get temporary OCS repairs completed, and the winter months of 2024 will provide valuable opportunities for practice.

(UPDATE 17 February 2024: it happened again and we're at two weeks and counting for the repairs)

To mitigate this risk: hold negligent tree owners financially liable for damage and delays caused by their trees falling on Caltrain, and aggressively trim back vegetation. Establish a well-equipped rapid response team of "squirrels" (OCS maintainers) who can quickly deploy to an incident site to perform temporary repairs that allow service to resume quickly. Keep this crew sharp by regular practice of repair methods, and stock an ample and ready supply of spare parts.

3. Grade crossing collisions - crossing wrecks are another frequent occurrence that will continue into the electric era, even if the new trains have much more powerful brakes that can avoid some collisions. With old diesels, you could cut, bend and weld beefy steel parts, quickly returning equipment to service. With an EMU, a collision can do more damage: crumple zones will crumple, and the fiberglass front-end mask and cladding will be potentially costly and time consuming to replace.

To mitigate this risk: improve crossing safety equipment and lighting, and grade separate the busiest crossings. Keep enough spare parts (including entire front-end masks) locally, so repairs don't require long lead times or a trip back to the factory in Utah.

4. Wheel flat spots in wet weather - while the new EMUs have the latest in computer-controlled braking technology, their swift acceleration and braking will put greater demands on controlling friction at the interface between wheel and rail. Throw in some moisture and crushed eucalyptus leaves, and even the best computer won't always get it right. It doesn't take much sliding of a wheel to create a flat spot, making that loud whomp-whomp-whomp sound. BART found this out the hard way, having to pause delivery of their new fleet while software changes were made. Caltrain's plans for a 75-minute local require very aggressive acceleration and braking, increasing the risk of flat spots.

To mitigate this risk: do lots of wet weather testing to find the limits of the software, and set limits to prevent train crews from driving too aggressively. Get lots of practice truing EMU wheels on the lathe.

5. Copper theft - there has already been a problem with thefts of impedance bonds, devices that allow traction return current (at zero volts) to cross signal block boundaries. These bonds are easily accessible on the track, but European railways have also experienced copper theft of live components energized at 25 kV by thieves who know their way around high voltage.

To mitigate this risk: secure valuable inventory, use identifying markings to prevent stolen copper from being easily sold for scrap, and maintain a large supply of spares to rapidly restore service in case of theft. Another job for the "squirrel" rapid response team.

In closing, it is commonly accepted that electric trains are more reliable than diesels, as one would certainly hope given how often Caltrain's decrepit fleet breaks down. Mechanical problems cause an average of 47 minutes of train delay every day, coming in third position after delays due to construction and trespassers. While new electric trains should bring this number down, electrification itself exposes service quality to new risks that Caltrain must anticipate and mitigate. Failing to control these risks can quickly turn electric revenue service into a fiasco. 2024 is the time for robust contingency planning.