ENDFIELD PURIFICATION FACILITY: WORTH IT?

If you’ve logged into Arknights: Endfield recently and spent the better part of an evening dragging conduits across half the map, congratulations — you’ve met the new purification facility mechanic, and you’re probably wondering the same thing every other Endmin is wondering right now: was any of this actually worth it?

The short answer is complicated. The long answer is what this entire breakdown exists to unpack.

The Test Area’s purification system is one of the most divisive additions to Endfield’s factory loop since launch. It promises a clever, eco-friendly way to convert your overflowing sewage output into usable Xircon Effluent, slot neatly into your Heavy Xiranite production lines, and shave hundreds of energy units off your power budget. On paper, it’s a love letter to optimization nerds. In practice, it’s a sprawling logistics headache that asks you to spend serious resources for an output rate that wouldn’t fill a thimble. This piece focuses on the one question the mechanics deep-dives skip: is it worth the cost?

TL;DR - Key Points

• ~1:30 effluent-to-sewage ratio — you pump roughly 180/min of sewage for only 6-13.5 Xircon Effluent per minute
• A full upgrade runs ~2 million Wuling stock bills plus secondary resources and a 1-2 hour setup slog
• The real payoff is power, not effluent — decommissioning Water Treatment Units saves ~300-400 energy and keeps you under battery breakpoints
• Extra effluent rarely helps a mature factory — battery output is bottlenecked by Originium Ore, not effluent supply
• Mind the facility caps — pipes, splitters, and convergers count against separate caps, and the 96/96 wall ambushes optimized builds
• Regional development points are the non-negotiable reason to upgrade — they feed directly into Wuling rank 15+
• It reads as prototype infrastructure for a future Sub-PAC, the rumored 1.4 gas mechanic, and a “Big Pipe” inter-zone fluid system
• Verdict: skip the conduits unless you love the puzzle — upgrade for the regional points, drain the pools, walk away

What Is the Purification Facility in Arknights Endfield?

The purification facility is a multi-stage industrial site located in the Test Area, the region introduced just south of the existing Wuling AIC zone. Unlike a standard Sub-PAC, it isn’t a fully buildable production area. Instead, it functions as a fixed, pre-built complex of Purification Nodes that you upgrade through your regional development tree.

Here’s the basic loop:

1. You pump sewage into the facility from elsewhere on your factory network using conduits.
2. The purification nodes process that sewage, splitting it into purified water (which is harmlessly dumped) and a small amount of Xircon Effluent.
3. The Xircon Effluent can then be piped back to your main AIC to be used as an alternative input for Heavy Xiranite production.

In return, you receive a roughly 1:30 ratio of effluent to sewage processed, plus the very real benefit of replacing several power-hungry Water Treatment Units with a single conduit manifold inlet.

It sounds elegant. The execution is where things start to fall apart. If you want a tier-by-tier throughput table and the underground-pipe-versus-manifold routing comparison, our full Purification Node mechanics analysis covers the engineering side in depth — this post is about whether the engineering is worth paying for.

The Setup: An Hour of Running Around (Minimum)

Here’s where the first frustration hits. The purification facility is not adjacent to any existing production zone. To use it, you have to lay a long, branching network of fluid conduits from your existing PACs all the way down to the Test Area, navigating terrain, cliffs, ziplines, and — depending on your factory layout — every single facility cap limitation you didn’t realize you had.

Most Endmins are reporting setups that take between 45 minutes and two hours of dedicated work, including:

• Teleporting between PACs to align input and output flow rates.
• Calibrating each sewage source to a steady flow rate of 2 to avoid bottlenecking the purification nodes.
• Discovering halfway through that your area pipeline capacity is at 96/96 and you can’t place any more conduits in the segment you’ve been planning around for the last twenty minutes.
• Reworking pipe convergers as workarounds because standalone pipe segments count differently against the cap.

That last point deserves its own warning. Pipes, splitters, and convergers count toward separate caps, which is an invisible mechanic the game doesn’t communicate clearly. If you’ve concentrated all your fluid processing in one outpost — Marker Stone is a common offender — you’re going to hit a wall and have to redesign chunks of your existing infrastructure to free up budget.

It’s a textbook case of a mechanic that punishes the players who took the time to optimize their factory in the first place.

The Output: Why the Xircon Effluent Feels Underwhelming

Once everything is finally connected and the sewage is flowing, you’ll discover that the actual production rate of Xircon Effluent is, well, modest.

A fully upgraded purification node operating at maximum saturation needs a sewage flow rate of 2 units per second per inlet — meaning you need roughly four sewage-producing facilities per node, and twelve total to saturate all three nodes in the facility.

The effluent output? At the current level cap, it’s hovering somewhere between 6 and 13.5 units per minute, depending on whether you’re also routing surplus Inert Effluent from your Heavy Xiranite lines through a Purifying Unit conversion.

For context, that’s enough effluent to produce maybe one extra battery per minute under optimal conditions — and only if you happen to have spare Originium Ore lying around to feed the rest of the recipe.

If you’re running a mature factory that’s already producing more goods than your outposts can sell as stock bills, this addition is functionally invisible. Your battery output is bottlenecked by Originium Ore, not by effluent supply, so adding more effluent doesn’t translate into more revenue.

Where it does help is if you’re running on a tight power budget. The purification facility lets you offload sewage processing from your main AIC, which means you can decommission several Water Treatment Units. Each one of those is a 60-energy drain, so replacing five or six of them can save you somewhere around 300 to 400 energy — enough to keep you under a battery breakpoint and reduce your long-term battery consumption.

That’s a real benefit. It’s just not a thrilling one.

Is It Worth the Two Million Wuling Stock Bills?

Let’s tackle the cost question head-on. Fully upgrading the purification facility through the regional development tree runs you somewhere in the neighborhood of 2 million Wuling stock bills, plus a smaller chunk of secondary resources.

Here’s the honest math:

If you’re chasing regional development levels, upgrading the facility is non-negotiable. Those points feed directly into your Wuling rank progression, and there’s no real shortcut.

If you’re a factory min-maxer, the power savings alone can justify the build. Staying under a battery breakpoint compounds over weeks of play, and the purification facility quietly turns a power-negative process into a power-neutral one.

If you’re a casual Endmin who’s already drowning in stock bills you can’t spend? Skip the conduits entirely. Upgrade the facility for the regional points, drain the pools for the quest reward, and walk away. The effluent isn’t going to change your life.

The Sub-PAC That Isn’t There (Yet)

The most common complaint about the Test Area isn’t the facility itself — it’s the conspicuous absence of a Sub-PAC anywhere nearby.

Walk around the Test Area for five minutes and you’ll notice the design language is screaming “this is a future production zone.” There are pools of Precipitation Acid scattered throughout. There’s a fresh Originium Ore deposit. There’s a Cuprium spot. There are visible houses across the lake that you get teleported away from if you try to approach them, strongly suggesting an unrevealed expansion area.

It looks, in every meaningful way, like a Sub-PAC zone that’s been built but not opened yet.

The prevailing theory in the community is that the current purification facility is a prototype — a preview of mechanics that will become much more useful once a Sub-PAC drops in the region in a future patch, allowing for local sewage generation and effluent production without the massive cross-map conduit logistics. The story also drops a “one month from now” timestamp during the relevant quest line, which feels like a deliberate setup for the next major content drop.

There’s also been chatter about a gas mechanic coming in the 1.4 update — the 1.3 livestream already teased a major AIC overhaul with gas products — which would dovetail neatly with the existing purification infrastructure. If gas processing requires similar fluid-style routing, the Test Area’s pre-built nodes could become a critical hub rather than an awkward outlier. Pair that with the rumored “Big Pipe” facility concept floating around theory threads — a hypothetical building that lets you transfer fluid between zones without manually laying conduits — and the entire Test Area starts to feel like a setup pitch for the next phase of factory gameplay.

We’re speculating, but the visual and mechanical breadcrumbs are unusually consistent.

Step-by-Step: How to Set Up Your Purification Facility Efficiently

If you’ve decided the trade-offs are worth it, here’s the most efficient route most Endmins have converged on after the dust settled.

1. Plan Your Sewage Source First

Before laying a single conduit, audit your existing factory. Find every sewage-producing line you have and check the total flow rate. You’re aiming for at least 180 units/min of sewage to make one purification node worth using; 540/min to fully saturate all three nodes (which is unrealistic for most factories without dedicating new lines to it).

The most common sewage producers are your Heavy Xiranite forges (each one outputs sewage as a byproduct), your Coprium lines, and certain Hetonite intermediate steps. Map them out before committing. If you never bothered taming your sewage in the first place, start with the Wuling sewage management overhaul and come back once your lines are stable.

2. Route Through the Wuling AIC, Not Marker Stone

If your fluid infrastructure is currently centralized in Marker Stone, the run to the Test Area is significantly longer and more conduit-intensive. Re-routing through the main Wuling AIC saves you a substantial amount of pipeline capacity and time. It’s a one-time pain that pays off in flexibility down the road.

3. Use Pipe Convergers as Trunk Lines

Because pipe convergers have a separate facility cap from standard pipe segments, building your trunk line as a chain of convergers rather than single pipes lets you push more fluid through the same area without hitting the 96/96 limit. This is the single most useful trick for anyone bumping against the cap.

4. Bottle the Effluent

The Xircon Effluent output rate is slow enough that bottling it in fluid tanks for later batch use is more efficient than trying to feed it directly into your Heavy Xiranite lines in real time. Buffer it. Use it in spikes.

5. Don’t Forget to Drain the Pools

There’s a small chest hidden inside the Qingbo Stockade’s sewage pit that’s easy to miss. Drain the pools for the quest reward, grab the chest, and pat yourself on the back for being thorough.

What the Test Area Tells Us About Endfield’s Future

Stepping back from the purification facility itself, the bigger story here is what the Test Area signals about Endfield’s design direction.

The game’s factory gameplay has been moving steadily toward more interconnected, cross-zone logistics. Early Endfield was about building self-contained PACs that produced what they needed locally. The introduction of cross-zone conduits, regional pipeline caps, and now a purification facility that requires cross-zone routing suggests the developers are pushing players toward a more continental supply-chain model.

That has real implications for how you plan your factory. The most efficient build a month ago — everything tightly packed in a single AIC — is increasingly the wrong build for the content currently being rolled out. Spread-out networks, redundant transit lines, and modular production cells are looking smarter by the patch.

If you’re building a new factory from scratch or considering a full rebuild ahead of the 1.4 patch, lean into modularity. The era of the monolithic AIC is ending.

Common Mistakes Endmins Are Making With the Purification Facility

A few patterns have emerged as the community has worked through the new system. Avoid these:

Trying to fully saturate the facility on day one. It requires twelve sewage-producing lines to max out, and most factories simply don’t have that much surplus sewage to spare. Run one or two nodes at partial capacity and call it good.

Routing effluent directly into Heavy Xiranite without buffering. The flow rate is too inconsistent and too slow. Bottle the output and use it in batches.

Forgetting about the regional facility cap. This is the silent killer. Check your facility count before you start laying conduits across the Test Area, or you’ll hit the cap mid-build and have to redesign.

Ignoring the power savings. Even if the effluent itself isn’t useful to you, the energy reduction from replacing Water Treatment Units is. Don’t dismiss it because the effluent is small.

Spending stock bills on full upgrades immediately. The regional development points are useful, but you don’t need to max the facility to get the bulk of the benefit. Upgrade to the level that unlocks the effluent loop, then assess whether further upgrades make sense for your specific factory.

The Verdict: Useful, But Underwhelming

So — was the new purification facility worth it?

For the majority of players, the honest answer is no, not yet. The effluent output is too small to meaningfully accelerate production. The setup is too tedious to feel rewarding. The stock bill cost is significant for a benefit that mostly manifests as a marginal power saving and a few extra batteries per hour.

But it’s also not nothing. The power savings are real. The regional development points feed into your overall Wuling rank progression. And every signal the game is sending — from the unused houses across the lake to the acid pools sitting in the open to the hints about gas mechanics in 1.4 — suggests that this is infrastructure being laid down ahead of a much bigger expansion.

If you enjoy the factory gameplay loop for its own sake, the purification facility is a fun afternoon of optimization puzzling. If you’re playing Endfield purely for combat, story, or character collection, you can safely upgrade it once for the regional points and ignore the rest.

The smart money says it’ll look a lot more worth it three months from now. For today, it’s a prototype dressed up as a feature — and prototypes are rarely the place to make your stand.

Frequently Asked Questions

How much sewage do I need to run the purification facility efficiently?

Aim for at least 180 units/min of sewage to make one purification node worthwhile. Full saturation across all three nodes requires roughly 540/min, which is unrealistic for most factories without dedicated production lines.

Can I use the Xircon Effluent for anything other than Heavy Xiranite?

Not currently. Xircon Effluent’s only meaningful use is as a substitute input for Heavy Xiranite production, replacing a fraction of the Xiranite normally required. Xircon itself has no other downstream applications at the moment beyond battery production.

Is upgrading the purification facility required for Wuling rank progression?

It’s not strictly required, but the regional development points from upgrading it contribute toward higher Wuling ranks (15+). If you’re chasing rank progression, you’ll want to upgrade it eventually regardless of how you feel about the effluent output.

Will the purification facility become more useful in future patches?

Almost certainly. The Test Area shows clear signs of being set up for future expansion, including space for a potential Sub-PAC, hints about gas mechanics in the 1.4 update, and unused terrain that strongly suggests additional content. Setting up the basic conduit infrastructure now means less work later.

Should I tear down my Marker Stone fluid processing to use the new facility?

Only if you’re planning a broader factory rebuild. Re-routing existing infrastructure just for the purification facility’s marginal output isn’t worth the effort. Wait for a bigger reason to rework your layout.

How much energy does the purification facility actually save?

Each Water Treatment Unit you decommission frees up roughly 60 energy. Offloading sewage processing to the facility typically lets you remove five or six of them, for a net saving in the 300-400 energy range — often enough to drop you under a battery consumption breakpoint.

Is the effluent worth more than the stock bills it costs to unlock?

Under ideal conditions the extra effluent translates to only about 2,000 stock bills of daily value, against a ~2 million stock-bill upgrade cost. The build pays for itself in convenience, power savings, and regional development points long before the effluent revenue ever does.

What’s the fastest way to dodge the 96/96 pipeline cap?

Build your trunk line out of pipe convergers rather than single pipe segments. Convergers count against a separate cap from standard pipes, so chaining them lets you push more fluid through a congested area without tripping the limit.

Have your own setup tips for the Arknights Endfield purification facility? The factory gameplay community is still figuring this one out together. Keep building, keep optimizing, and watch the 1.4 patch notes — that’s when this prototype either grows up or gets quietly retired.