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The Vault - Fallout Wiki
The Vault - Fallout Wiki
Battle of Project Purity
Liberty Prime ffd.jpg
LocationJefferson Memorial, Capital Wasteland
ResultBrotherhood seizes Project Purity
Enclave forces routed
Involved parties
BoS Flag FO3.png Lyons' Brotherhood of SteelFo3 Enclave State Flag.png Enclave
Elder Owyn Lyons
Sentinel Sarah Lyons
President John Henry Eden
Colonel Augustus Autumn
Liberty Prime
Lyons' Pride
Supporting Knights and Paladins
Enclave soldiers
Vertibird air support
Artillery support
Connected events
Part of:
The Purifier Conflict
Assault of Fort Bannister

Battle of Project Purity was a decisive confrontation occurring in 2278 between the Lyons' Brotherhood of Steel and the Enclave, focusing on Project Purity at the Jefferson Memorial.


The origins of the battle lie in the person of James, the founder of Project Purity, who, after 19 years of seclusion in Vault 101 discovered a way to bring the project online. Thanks to help from their child, James was able to reactivate the project and begin preparations for the integration of the Garden of Eden Creation Kit. However, the Enclave, led personally by Colonel Augustus Autumn immediately seized the Project. Unwilling to hand the project over to the Enclave, James committed suicide by releasing a blast of deadly radiation inside the control chamber, intent on crippling the facility and killing the Colonel. He failed at both.[1]

The seizure of the purifier and arrival of Dr. Madison Li at the Citadel with information that the Purifier can be made functional, despite previous data to the contrary, started the chain of events that led to the battle. Elder Owyn Lyons decided that having Enclave in control of the wasteland, thanks to a stable supply of purified water from the Jefferson Memorial facility, cannot be allowed.[2][3] To this end, he began to muster what little forces he had and gear them up for a campaign against the Enclave, while assigning the Lone Wanderer to retrieve the key to Project Purity: The Garden of Eden Creation Kit from Vault 87. Meanwhile, Madison Li and Scribe Rothchild set out to devise a way to make Liberty Prime operational.[4]

The Lone Wanderer's mission did not go as planned. The Enclave managed to infiltrate Vault 87 some time prior and captured the Lone Wanderer and the G.E.C.K.[4] However, due to President Eden and Colonel Autumn's disagreements, the Lone Wanderer escaped Raven Rock and regrouped with Lyons' forces at the Citadel. Despite having barely enough men to keep the Citadel defended,[5] Elder Lyons ordered the freshly activated, jury rigged[6] Liberty Prime to be deployed, covered by the Lyons' Pride, in order to prevent the Enclave from activating the purifier.[7]

The battle

Liberty Prime was released just outside the entrance to the Citadel and begun making his way towards Project Purity over the Arlington Memorial bridge. The massive robot acted as a spearhead, destroying Vertibirds and entrenched Enclave positions with ease. The Enclave was entirely unprepared for such an offensive and could not counter such brute force, even with Vertibird strafing runs and artillery bombardment.[7]

Lyons's Pride and the Lone Wanderer followed the robot's path of destruction, mopping up any Enclave personnel that survived the initial assault. Liberty Prime continued his assault up to the Purifier, destroying photonic resonance barriers set up around the island to deny land access. Upon arrival at the Memorial, Liberty Prime and the Pride set up a security perimeter, while Sarah Lyons and the Lone Wanderer headed inside the facility.[7]

After eliminating the remaining Enclave defenders, the pair confronted Colonel Augustus Autumn in the purifier control chamber. After dealing with him (it is not known whether the Colonel stood his ground or was convinced to live), the purifier was activated and began the purification process of the D.C. tidal basin.[7] The activation came none too soon, as the damage the facility sustained in the course of the battle caused pressure to build up and nearly led to the facility being destroyed.[8]

However, the shockwave that occurred as the facility activated caused severe trauma to both Sarah Lyons and the Lone Wanderer,[7][9] putting them in a comatose state. The Lone Wanderer would regain consciousness two weeks later, with Lyons several days later.[10]


The battle was a crucial point in The Purifier Conflict, as the Brotherhood managed to take one of the main strongholds of the Enclave in D.C., while simultaneously destroying a large part of their military force, in terms of both manpower and ordnance. Liberty Prime also became a key element of their counter-Enclave strategy, bridging the technological power gap between them and the Enclave.[10]

The defeat at the purifier also threw remaining Enclave forces into disarray, allowing the Pride and other Lyons units, supported by Liberty Prime, to destroy several key installations throughout the wastes, first and foremost being Raven Rock.[11] With it lost, Enclave remnants in the Capital Wasteland became disorganized and uncoordinated, making it easier for the still weak Brotherhood to openly attack and rout them, particularly with Prime's support.[12]

A second major change in the landscape was the appearance of water caravans. Elder Lyons made the decision to provide water to all major settlements in the wasteland, completely free of charge.[13] Elder Lyons' insistence on providing water for free has made finding resources and funding for the operation extremely hard. So hard in fact, that they forced Scribe Bigsley, the man in charge of the entire venture, to go against his orders and sell water, in order to actually be able to accomplish what he's been ordered to do.[14][15] Another problem was that bottling water had to be accomplished manually, as the Brotherhood is too preoccupied with reverse-engineering Enclave tech to devise a bottling machine.[16] The entire operation was also severely hampered by a general lack of resources and planning.[17][18]


The Battle of Project Purity appears only in Fallout 3.


  1. Waters of Life
  2. Owyn Lyons: "Madison, I'm surprised to see you here. What can I do for you?"
    Madison Li: "Don't talk down to me, Lyons. I had nowhere else to turn. You must help us. Project Purity has been overrun."
    Owyn Lyons: "Yes, I'd heard reports of an incident there. What details can you give us?"
    Madison Li: "The Enclave. They've attacked Project Purity. James is dead... there may be more. I don't know. You have to do something!"
    Owyn Lyons: "Then it's as we feared. Madison, I'm sorry this happened. I wish we could have done something..."
    Madison Li: "Then do something now! They've taken over the purifier. Lyons, they cannot be permitted to have control over it. It's not right!"
    Owyn Lyons: "Now now, calm down. You know as well as I do that the purifier doesn't work. It's useless to them. Perhaps it's time to walk away."
    Madison Li: "That's not true. James... He found what's been missing. We know how to get it running."
    Owyn Lyons: "Is that so? Does the Enclave know this?"
    Madison Li: "No, I don't think... I don't know. I just don't know what's happening anymore."
    Owyn Lyons: "All right, Madison. It'll be okay. Now, this is James' son/daughter, I presume? I can see the resemblance."
    Madison Li: "Yes. He/She knows what we need. Vault-Tec computer, something to locate equipment. Please help him/her."
    Owyn Lyons: "Very well. We'll sort this all out.".
    (Madison Li's and Owyn Lyons' dialogue)
  3. Elder Owyn Lyons -- personal log: "I cannot - I will not - allow the Enclave to control the one thing that could bring even the slightest spark of hope to these people. Project Purity would mean millions of gallons of pure, clean water for the people of the Capital Wasteland. James never got the damned thing to run. Neither did we, for that matter. But the Enclave...If they controlled that much clean water...they would control the entire Capital Wasteland. I simply cannot allow that to happen."
  4. 4.0 4.1 Finding the Garden of Eden
  5. Sarah Lyons: "I don't like it."
    Owyn Lyons: "You don't have to like it, Sarah. You just have to follow orders."
    Sarah Lyons: "So we just wait until they decide we're next on the list? If the Pride goes in now, we might have a chance."
    Owyn Lyons: "And if you fail, then what? The risk is not worth the reward."
    Sarah Lyons: "All I'm saying is, the longer we sit here, the more time they have to shore up their defenses. We should hit them sooner rather than later."
    Owyn Lyons: "We barely have the manpower to keep the Citadel fortified. We've been over this before, Sarah..."
    (Reginald Rothchild's, Sarah, and Owyn Lyons' dialogue) Note: MQ09ElderSarahConv
  6. Owyn Lyons: "Then it's decided. Sarah, you take the Pride and use the robot as support. Take our friend here and secure that purifier."
    Reginald Rothchild: "It's not ready for field tests, let alone live fire situations. The weapons haven't been calibrated, the navigation detection system is offline..."
    Owyn Lyons: "Rothchild, enough. Can you make it work?"
    "What? No! I mean, Li and I have solved the power problems, but we've only barely finished diagnostic tests."
    Owyn Lyons: "So?"
    (Reginald Rothchild's, Sarah, and Owyn Lyons' dialogue) Note: MQ11ElderSarahConv
  7. 7.0 7.1 7.2 7.3 7.4 Take It Back!
  8. Madison Li: "Hello? Hello?... Is anyone there? It's Doctor Li. Something's wrong with the purifier... Please, someone answer!"
    "If you don't activate the purifier right now, you're all going to die!"
    "Why haven't you started the purifier? Please, do it now!"
    "You only have about a minute left! Please hurry!"
    "If you're still there, the purifier needs to be activated NOW! You don't have much time left!"
    (Madison Li's dialogue)
  9. The Lone Wanderer: "What's going on?"
    Owyn Lyons: "It's all right, you're safe now. You're in the Citadel. There was some sort of energy spike as the purifier started. You and Sarah were knocked unconscious, and brought here to the infirmary. We've been watching over the two of you for days. I'm glad to see it's paid off."
    (Owyn Lyons' dialogue)
  10. 10.0 10.1 Broken Steel events.
  11. The Lone Wanderer: "What else can you tell me about the fight against the Enclave?"
    Owyn Lyons: "As you know, I had my reservations about engaging the Enclave. They did not directly attack us, and I believed we had time. Time to be cautious. Their assault on the purifier forced our hand. We had no choice but to engage them directly. And, once that engagement had begun, we could do nothing but see it through to the end. If they had not considered us a threat before, they do now. So we have spent the time since you and I last spoke systematically locating and destroying every bastion of Enclave force we can. Liberty Prime has proven far more successful than any of us could have hoped for."
    (Owyn Lyons' dialogue)
  12. The Lone Wanderer: "Has the Enclave been putting up much of a fight?"
    Tristan: "After we secured Project Purity, Liberty Prime was unleashed on their headquarters. It was a quick fight. Since then, their operations have been severely disrupted. We're trying to use that to our advantage -- we keep hitting them while they're down. We can't give them a moment to breathe safely, or else they might pose more of a threat to us in the long run."
    (Tristan's dialogue)
  13. The Lone Wanderer: "Seems like a lot of trouble giving it away. Why don't you just sell the water?"
    Bigsley: "Many of us keep asking that same question. The Brotherhood isn't a postal service. We have IMPORTANT things to do, and we need caps and technology to do it! Lyons is on some kind of mission. Has he forgotten about the Enclave? That's our priority... But yeah. Things are being done to "offset" the cost of Lyons' little pet "Purity" project."
    (Bigsley's dialogue)
  14. The Lone Wanderer: "Griffon's up to something with the Aqua Pura. What do you know about it?"
    Bigsley: "Not that it's really any of your business, but we have an arrangement. He buys water, I send him some. I use the caps and tech he pays me to fund the other water deliveries. I send my men with the water to the Museum Authority in the Mall. Griffon sends the payment back with my men. So far, so good. Lyons wouldn't approve, but I don't really care anymore. I need the resources and there's certainly plenty of water to go around."
    (Tristan's dialogue)
  15. Scribe: "They're a week late, sir. Should we send out a search party?"
    Bigsley: "For a couple of Wasteland hustlers and a pack Brahmin?"
    Scribe: "What about our men?"
    Bigsley: "I'm not wasting any more resources."
    Scribe: "Yessir."
    Bigsley: "If Lyons wants to chase after his deliveries, fine. Let HIM do it. But I'm done wasting resources and risking lives on this pet project of his."
    Scribe: "For what it's worth, you aren't the only one who feels that way."
    Bigsley: "Thank you. Now, kindly get the hell out of here. I need to think."
    (Scribes' and Bigsley's dialogue) Note: The following prompts and responses are selected randomly in DLC03WQBigsleyScribeConv07
  16. The Lone Wanderer: "Is it hard bottling all that water? Or is it all done by machines?"
    Bigsley: "You take a bottle, you dunk it under water, and glug glug glug, it fills up. Amazing. But you're right a machine would help. But all the Scribes are busy reverse engineering Enclave gear. A machine that puts water in bottles just isn't on anyone's priority list at the moment."
    (Bigsley's dialogue)
  17. The Lone Wanderer: "Sounds like you have your hands full."
    Bigsley: "Everyone was so excited about that Purifier: "Project Purity this," and "Project Purity that." But did anyone stop to ask, "Hey, what are we going to DO with all that clean water?" Well, guess who gets to fill in that tiny detail. It'd be one thing if I had support, but that little war with the Enclave has depleted much of the Brotherhood's resources. And to top it off, I have to be mommy to a bunch of lab coats."
    (Bigsley's dialogue)
  18. The Lone Wanderer: "You're not the only one with problems."
    Bigsley: "Right. I heard about your dad. Sorry kid. I don't mean to sound unsympathetic, really. But, if you understood the pressure... You know the Wasteland. Imagine trying to get fresh water to every known settlement, without getting it stolen by Raiders or Mutants. Now imagine doing that without any trained soldiers or military resources because they've all been exhausted fighting a little war with the Enclave. Yeah. That's MY job. Not to mention the mountain of crap I get from all the lab coats running around underfoot."
    (Bigsley's dialogue)