Need a Hydroelectric Dam walkthrough for The Last of Us 1, including all collectibles? In this The Last of Us 1 guide, we're going to show you how to achieve 100% completion in Hydroelectric Dam, which is part of the Tommy's Dam chapter.

There are 2x Artefacts, 1x Firefly Pendant, 1x Comic, 1x Training Manual, 1x Workbench, 1x Shiv Door, and 4x Optional Conversations to find in Hydroelectric Dam, as Joel and Ellie finally catch up with Tommy.

The Last of Us 1: Hydroelectric Dam Walkthrough

The Last of Us 1: Hydroelectric Dam Walkthrough - All Collectibles: Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, Optional Conversations
Image: Push Square

With the Suburbs long behind you, it's time to push on to the Hydroelectric Dam. To begin, simply walk along the muddy track until you reach a crashed Jeep on the left of the trail.

Weapon: El Diablo

The Last of Us 1: Hydroelectric Dam Walkthrough - All Collectibles: Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, Optional Conversations
Image: Push Square

Next to the crashed Jeep at the very start of the chapter, there's a skeleton on the ground. Just to the left of the remains is a new Weapon named the El Diablo.

Take the path to the left of the Jeep down the hill towards the river, and climb up over the rock formation towards the bridge.

Comic #1: Foreign Element

Before you go under the bridge, look to the hill on your right and at the top you'll see an upside down crashed car. Just in front of this is a Comic named Foreign Element.

Continue forward under the bridge to the Hydroelectric Power Plant, and make your way up the metal staircase.

Shiv Door #1

The Last of Us 1: Hydroelectric Dam Walkthrough - All Collectibles: Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, Optional Conversations
Image: Push Square

At the top of the metal staircase, just to the right, is a grey metal door. This is another Shiv Door, so open it up and loot all the supplies inside, including the Supplements.

Once you're done, head back outside and interact with the big red wheel. Turn it to close the dam halfway. Dive into the water, and look for the building at the bottom. Head in through the open window and dislodge the wooden pallet by pushing the triangle button. Now swim back to the surface.

Ferry the wooden pallet to Ellie so that she can climb on, and then take her to the other side, where the other red wheel is. She'll climb up and turn it, creating a bridge across to the other side for Joel.

Optional Conversation #1

Once you reach the other side of the bridge, after Ellie's turned the wheel, you can choose to give her a high-five with triangle. If you don't, then you'll get the Left Hanging Trophy. Then, drop down to the campsite on the left and find the grave with a teddy bear next to it. Interact with it for an Optional Conversation opportunity.

Make your way up over the rock formation and closer towards the power plant. You'll need to duck under a collapsed tree branch along the way. Before you head inside the power plant, look inside the outpost office for supplies.

Artefact #1: Power Plant Map

Inside the outpost office, once you reach the main gates to the power plant, you'll find an Artefact named Power Plant Map pinned to the wall.

Once you've grabbed everything head to the gates and prepare for a touching reunion with a familiar face. Enjoy the cutscene, and then follow Tommy into the power plant.

Optional Conversation #2

The Last of Us 1: Hydroelectric Dam Walkthrough - All Collectibles: Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, Optional Conversations
Image: Push Square

When Ellie rushes over to the horse, this will trigger an Optional Conversation opportunity, so be sure to respond to the prompt. You can also pet the horse yourself if you want to. (We're going to assume you do.)

The Last of Us 1: Hydroelectric Dam Walkthrough - All Collectibles: Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, Optional Conversations
Image: Push Square

Follow Maria into the main power plant building, and split up from Ellie so you can have some alone time with Tommy.

Optional Conversation #3

Once you're alone with Tommy, he has something to show you, triggering an Optional Conversation opportunity. He'll give you a photograph of you and Sarah.

Head up the stairs following closely behind Tommy. Go in the room on the left at the top of the stairs, opposite the door Tommy goes through. There are a lot of supplies in here, including Supplements and Weapon Parts. Once you're done, head through the door behind Tommy.

Optional Conversation #4

The Last of Us 1: Hydroelectric Dam Walkthrough - All Collectibles: Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, Optional Conversations
Image: Push Square

Patrolling the bridge on the right is a woman with a rifle on lookout. She'll point out that "you're new around here", triggering an Optional Conversation opportunity.

Training Manual #1: Smoke Chemistry

Continue to follow Tommy, ensuring to pet Buckley along the way for the Who's a Good Boy? Trophy. Be sure to collect the Supplements in the control room, and then grab a Training Manual named Smoke Chemistry from the turned over locker. This will be on the corner of the main console in The Last of Us and The Last of Us Remastered.

Workbench #1

The Last of Us 1: Hydroelectric Dam Walkthrough - All Collectibles: Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, Optional Conversations
Image: Push Square

You'll find a Workbench just adjacent to the room with the control panel, next to where you found the Training Manual called Smoke Chemistry.

Firefly Pendant #1: Oliverio's Firefly Pendant

Head down the metal staircase from where the Workbench was, into the main turbine room, and through the doorway underneath where you came in. Between some filters, you'll find a Firefly Pendant named Oliverio's Firefly Pendant on the floor. There are also some Weapons Parts in this room.

Once you're done with all the collectibles and supplies in this area, follow Tommy through the door at the far-end of the turbine room. This is your opportunity to finally chat one-on-one with your brother. Unfortunately, you'll be interrupted by an alarm, and it's time to fight your way back through the turbine room. Remember to take cover, and aim for the head where possible. Take the staircase up at the end of the room back into the control room.

Artefact #2: Plant Schematics

Before you leave the control room, be sure to grab an Artefact named Plant Schematics from the square table in the middle of the room.

Outside of the control room, continue to fight your way across the bridge, carefully and precisely. There's an axe on the ground you can pick up if you're in need of a melee weapon. Follow Tommy through the door and down the stairs, dealing with any bandits as you go.

The Last of Us 1: Hydroelectric Dam Walkthrough - All Collectibles: Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, Optional Conversations
Image: Push Square

Once you've killed them all, Ellie will call out to you, so head over to her and Maria's position. Watch the cutscene, and then prepare yourself to move on to Ranch House.

Did our Hydroelectric Dam walkthrough for The Last of Us 1 help? Did you find all Artefacts, Firefly Pendants, Comics, Training Manuals, Workbenches, Shiv Doors, and Optional Conversations? Check out our The Last of Us 1 guide for much more information on the game, including all collectibles.