The Sewers in Resident Evil 3 is crawling with Hunter Gammas and there’s only one way to escape, finding the battery pack to unlock doors.
Resident Evil 3 Battery Pack Location
The Battery Pack can be found in the Lab on the far-left side of the Sewers. To start, make sure to grab the Sewer map in the Manager’s Office at the start of the area.
Walk down the path from the Manager’s Office and take a slide down the drain. Once on the bottom level fight your way through until the fork in the tunnel system. If you take the right tunnel, it will take you to the Lab. Going down the left tunnel will lead you to an Office with the MGL Grenade Launcher.
The Battery Pack will be sitting on a table in the Lab. Once you grab the Battery Pack, head out and climb the ladder to the stairs and use it on the locked door. Go through the door and fight the Hunter Gamma that jumps up and unlock the gate on the left.
Go back around through the gate and grab the Battery Pack from the door. The Security Room is also housed on the upper level in the Sewer and you’ll need to unlock it with the Battery Pack to get the Hip Pouch and other supplies inside.
Once you’ve cleared the area, head back to the gate, go down the ladder, and place the Battery Pack in the slot near the final door. You’ve now successfully navigated the sewers and are ready to progress.