People in the San Francisco Bay Area were forced to seek public transit alternatives after BART experienced a big outage on Sunday morning

• The Bay Area Rapid Transit system experienced an outage on Sunday, and riders were encouraged to use other Bay Area transit alternatives.
• The cause of the outage was a failure in its field network devices, which manage the energy distribution for the electric grid used by BART.
• These outages are fairly uncommon, with the last one of this scale happening in 2019.
• BART service has since resumed.

The Bay Area Rapid Transit system is back after experiencing issues over the weekend.

On Sunday, the BART system experienced a large outage after its "field network devices failed," according to the transit company, causing the system to shut down. The devices normally manage the energy distribution on the electric grid that the BART system uses to operate its trains, which many in the San Francisco Bay Area rely on for daily transportation.

While BART was down, other regional transit services like Muni and AC Transit were functioning normally, and riders were encouraged to consider these alternatives, according to a press release. Those other services cover different areas than the BART, but do have some shared stations.

The transit system, launched in 1972, experienced outages from around 5:10 a.m. to 12:20 p.m. local time, with service returning to the East Bay 40 minutes earlier, at 11:40 a.m. Pacific Time.

Cisco, official vendor for the BART system, operates the field network system that was hit with the outage. Business Insider has reached out to Cisco for more information on the outage.

"Engineers have implemented a configuration change to the network which is expected to protect against future device failures that could potentially shut down the system," an update posted to BART's website said when service was restored.

Ridership, which is normally down on the weekends, still sees about 20,000 people on Saturdays and Sundays. Overall numbers are down around 80% because of the pandemic.

While there haven't been major changes to the transit system because of coronavirus, the transit system is running long trains to help with social distancing and masks are required for riders.

Major disruptions are relatively uncommon for the system, with the last outage occurring in 2019, and before that, 2006.