Light Rail Service Disruption FAQs

April 22, 2018 General, SacRT in Community

What is a light rail service disruption?

A light rail service disruption is when an incident occurs that makes it unsafe or impossible for the light rail train to pass through an area. Light rail service will most often continue in areas outside of the affected area.

Although the actual incident may be confined to a small area, it may disrupt service to other light rail stations along the line. This is due to the way the light rail trains function and operate.

Power is provided to the system by traction power substations (TPSS) located throughout the system. When an incident occurs, sometimes an entire section of track between substations needs to be shut down in order to safely work on the problem. Therefore, light rail trains may be stopped further out from where the actual incident occurred.

Additionally, the light rail trains that are still in service need to able to turn around to serve both directions of travel on either side of the disruption. Although the issue may be at one specific location, multiple stations are out of service. The light rail system has specific and limited locations that allow for trains to turn around.  The length of a disruption will often be extended to these locations allowing for light rail trains to turn safely.

During a small disruption, service will be delayed until the problem can be fixed. However, when a major service disruption occurs that is expected to prevent train movement for a longer period of time, a bus bridge (dedicated buses) is used to transport passengers to their destination station, or to a station where they can once again board an operational train.


How does a bus bridge work?

When there is a light rail service disruption for an extended period of time, a bus bridge is put into place. A bus bridge is when buses are used to transport SacRT passengers when light rail trains cannot, creating a “bridge” around the service disruption area. SacRT staff creates bus bridge routes between locations where buses can get close to the affected light rail stations for the most efficient transfers.

The bus bridge buses will stop at each station close to where the light rail train would have stopped, allowing passengers to board and alight as needed. At the end of each bus bridge, riders can board operational light rail trains to take them to their destinations.

Unfortunately, SacRT does not have a dedicated staff of extra bus operators or a special fleet of extra buses to accommodate a bus bridge. This means that bus operators and buses are pulled from their regular bus routes to transport light rail passengers. SacRT works quickly to pull resources for a bus bridge. Sometimes this results in less frequent bus service in certain areas.

Depending on the time of day a light rail service disruption happens, it may take 30 to 45 minutes for the buses to arrive at the affected stations. It’s important that passengers, affected by the service disruption, listen for direction from SacRT staff at the station platform on where to go and which buses to board. Bus bridge buses will be marked with “Shuttle” or “Bus Bridge” on the head sign. It’s also important to note that the special buses are not able to operate on a light rail schedule since the buses travel on surface streets to pick up and drop off passengers at the affected light rail stations, and may be impacted by vehicle traffic.

If you have any questions on where to go to board a special shuttle bus, or what bus to board, ask a uniformed SacRT employee.

We also ask for your patience towards bus operators. They are doing their best to get riders to their destination safely and efficiently. However, they are driving routes that are not regular bus routes and they may not be as familiar with the bus bridge route. We also ask for your patience in continuing your trip. Buses carry fewer passengers then trains so it can take time to move all of our customers affected by a service disruption.  Particularly during high ridership periods (peak commute times), you may see a number of very full buses pass you before there is room for you to board.


How do I get information during a service disruption?

SacRT does its best to communicate accurate information to customers in a timely manner during a service disruption. However, due to unforeseen circumstances, information may change quickly without advance notice. In addition, SacRT staff has to make sure the information is accurate, which may involve coordination with other departments before posting a message or sending out an alert.

Service disruption information will be posted to the electronic message signs (EMS) at the light rail stations. These are the black signs with color text that are displayed above the station platform. SacRT will make every attempt necessary to update the EMS as quickly as circumstances allow.

For light rail alerts, riders are encouraged to download the free “Alert SacRT” mobile app from the App Store or Google Play. Additionally, we encourage riders to follow SacRT on social media. Even if you do not have an account, you can still view SacRT’s Facebook and Twitter pages. Note that SacRT staff may not be able to respond in real-time to messages sent on Facebook or Twitter. And, for service disruptions that occur outside of regular business hours, it may take staff a little longer to gather the information and post it.



Customer Service: 916-321-BUSS (2877) – Monday through Friday from 6:30 a.m. to 6:30 p.m.

Security Operations Center: 916-556-0275


What could cause a service disruption?

There are a variety of other incidents not involving SacRT that could impede train movement. This could include a vehicle accident not involving a light rail train that is blocking the light rail tracks. Police activity in a certain area, or a fire could also make it unsafe for light rail trains to operate. A public utility outage, due to either a storm or human error, could cause SacRT to lose power and make trains inoperable.

There are also a number of operational problems that could lead to a service disruption, some of these include:


The overhead cantenary system (OCS) is a complex system that distributes the power to the train via messenger cables and contact wires. The train collects the power from the contact wire through the pantograph (the flat triangular piece on top of the train). As temperatures increase above 100 degrees, the OCS will reach its design limits and can be subject to malfunction.

During the extreme summer heat, SacRT will slow the speed of the trains to reduce the chance of OCS issues. Additionally, these wires receive yearlong maintenance to make sure that they are well maintained and in the best working order they can be. Slower speeds may impact the light rail schedule.

Impassable Track

Like many materials, the metal on the SacRT track system is subject to contraction and expansion based on the temperature. During times of high heat, it is possible for a 1,000 foot stretch of track to expand by as much as eight inches. Extreme temperatures could inevitably cause failure at a switch, bridge or crossing. To prevent these problems, SacRT will implement speed restrictions so that the system can continue to operate safely. These speed restrictions can result in minor schedule delays to train service. Normal operation resumes once the temperature drops.


Like automobiles, light rail trains have thousands of mechanical parts. These parts all work together for the train to operate safely. The malfunction of any one part could potentially take an entire train out of service.

Accidents and Other Emergencies

Occasionally, SacRT experiences issues where there is a collision between a light rail train and a vehicle, bicyclist, or pedestrian. Unlike cars, light rail trains cannot swerve or veer off the tracks to prevent a collision. Even when the emergency brake is applied, it can take 600 feet or more for a light rail train stop. That’s the length of two football fields.

SacRT takes safety around tracks very seriously and asks all drivers, cyclists and pedestrians to be extra cautious around the tracks and pay close attention to the warning signs and signals. Safety is a shared responsibility. SacRT encourages riders to read the safety information found at


Why does a major service disruption take so long?

Whenever there is a major service disruption, SacRT’s number one priority is safety. If necessary, emergency responders are dispatched. SacRT also immediately dispatches staff to a service disruption as needed including Transportation Supervisors, Transit Officers, Transit Agents, Safety Specialists, Maintenance staff, etc.

Once the problem is diagnosed, crews begin doing what is needed to remediate it. Some problems are so complex that it takes a measurable effort and a methodical process to perform the repairs safely. SacRT has a specialized crew that is trained on how to measure, understand and work around the deadly hazards that can be involved in repairing the light rail system. Additionally, they must effectively communicate with all team members that are stretched along miles of light rail track.

One of the biggest safety concerns regarding working on the light rail system is electricity. The incoming amount of power that SacRT receives from SMUD can be as much as 21,000 volts AC. In many cases, power must be shut down and grounded before any work can be done. Turning the power back on must also be done safely and requires testing. This can take an extensive process that must be done properly from start to finish and involves lots of safety protocols.


What other transportation options do I have when there is a major service disruption?

If you have alternate transportation options, this might be a good time to use them. During a major service disruption, you may wish to consider driving, walking or biking to your destination. Perhaps try to get a ride with a friend or family member. SacRT would also encourage riders to look into ride sharing services such as Uber, Lyft or even a traditional taxi service.


Why are there still delays after service resumes?

After light rail service resumes, there may still be some residual schedule delays on the system. This is simply a matter of catching up service to meet the actual schedule. During a service disruption, trains can get backed up in a certain area. When service resumes, light rail trains start working their way back through the system. However, this can take some time, especially in downtown Sacramento, where SacRT must abide by other traffic signals to operate safely. SacRT tries its best to move passengers quickly and efficiently to their destinations during and after a service disruption.

To submit comments, concerns and compliments, email us at or call SacRT’s Customer Advocacy department at 916-557-4545.