SAN FRANCISCO (KGO) -- Treasure Island was the site of a powerful earthquake on Tuesday. It was part of an exercise to simulate major damage to gas lines from a future quake.
Smoke, flames and sounds of gas released from nearby damaged lines in the neighborhood.
While it is just a drill, San Francisco Fire Chief Jeanine Nicholson says this is just part of the damage the city could see in the event of an earthquake.
"A 7.0 earthquake, we're going to have a lot going on. Multiple fires, multiple wires down, multiple people injured and trapped," she said.
MORE: Will SF's Golden Gate Bridge survive the next big earthquake? USGS details new threat
It's something firefighters train year-round for.
But on Tuesday, about three dozen PG&E workers came to train with them on Treasure Island.
"Part of it is learning to speak the same language so that we can communicate more effectively in the event of a real-world emergency," said Jason King, PG&E spokesperson.
"Practicing a response in a controlled environment like this will help us be more effective in making communities safe in a real-world event," he said.
MORE: ShakeAlert earthquake warning system now uses GPS data to determine magnitude
PG&E crews focused on damaged gas lines and downed power lines, responding to several different scenarios, and learning how to effectively team up with emergency workers.
"We're going to have to learn to be nimble and be nimble in our coordination with the San Francisco Fire Department in an event like this," said King.
MORE: Fault line that caused 2014 Napa quake longer, potentially stronger than previously thought: USGS
Chief Nicholson says the goal of this exercise is to find both strengths and weaknesses between PG&E and first responders.
"It's imperative that we do this in real time today because that is what will be expected of all of us when the big one hits. So we're not just walking through and pointing things out, we're practicing like we're going to play," said Chief Nicholson.
Because she says, it's not a matter of if, but when the next big one hits.
Click here for the latest stories and videos about earthquakes here in the Bay Area and around the world, and click here for more information on disaster preparedness.
RELATED STORIES & VIDEOS: