Project Tomorrow Survival: Oxygen, Water and Food

Project Tomorrow is not a hardcore survival game. You will not die of thirst in the first ten minutes, and the starting region gives you enough supplies to learn the systems. But the survival meters are the reason the map has a shape: green ground is safe, purple ground costs oxygen, and every trip outside the base is a timed errand.

This guide explains each meter, how to refill it, and how to plan an expedition that does not end with a corpse in the wasteland.

The three meters

The demo displays three survival stats:

• Health — reduced by enemy attacks, dirty water and hazards. Restored with medical items and time inside a safe base.
• Hydration — drains over time and faster during exertion. Restored by drinking clean water.
• Oxygen — stable in lush areas, drains in barren areas, restored when you return to green ground or a sealed base.

The release build adds food production and settlement needs in Tidehaven. The exact UI may add or rename a meter, but the underlying loop is the same: consume supplies, produce replacements, and keep a reserve for the trip home.

Oxygen is a geography problem

Oxygen is the most important early meter because it changes how you read the map. Inside the green zone around your oxygen emitters, the meter is neutral. Step into the purple wasteland and it begins to fall. Return to the green and it recovers.

That makes terraforming a survival tool, not just a victory condition. Every oxygen emitter extends the safe area. Every hydro infuser spreads the green further. The first cluster is not only an economy investment; it is the range in which you can gather without a timer.

Three rules follow:

1. Never enter the wasteland without a return plan. Note the distance to the green edge before you start gathering.
2. Carry an oxygen supply. The crafted oxygen supply unit refills the meter in the field. It is cheap insurance and worth one inventory slot.
3. Do not fight in the purple. Combat slows you down and extends the time outside the green. Pull enemies back to your turrets.

Oxygen emitters are also targets. If a wave destroys the emitter that anchors your safe zone, the green shrinks. That is a defensive problem first and a survival problem second.

Hydration and water

Hydration drains continuously and faster when you sprint or fight. Drinking dirty water restores hydration but damages health, which is a bad trade in a fight. The correct fix is clean water.

Early on, you can find water in supply crates and produce it with a Hydro Infuser and water-production buildings. In Tidehaven, the game expects you to build a water chain rather than live off crates. The patch notes for that region specifically call out food and water production as a new layer, with fewer supply boxes to force self-sufficiency.

A practical water plan:

• Keep two clean waters in your inventory before a long expedition.
• Build one water production building as soon as the Hydro Infuser is stable.
• Store a reserve at base; do not drink the last unit before a wave.
• If you find dirty water, purify it rather than drinking it. A medical item costs more than the purification time.

Water is also a base resource for terraforming and housing. Do not spend the entire reserve on construction and then leave your character thirsty. Keep a buffer.

Food and health

Food appears as rations and crafted meals. In the demo, rations are consumables; in Tidehaven, food production becomes a base system alongside water. Settlements and population add another consumer, though the release build's exact consumption rates are not published.

Health is the meter you notice last and miss first. Medical items restore a chunk of health; staying inside the base restores it slowly. Do not save a medical item for a "better moment" during a wave. If you are below half health and the wall is about to break, use it.

A useful baseline for the first region: one medical item, one oxygen supply, two clean waters and two rations in the inventory before any expedition that leaves the green zone.

How to build a self-sufficient supply chain

The transition from scavenging to production happens in this order:

1. Water — a Hydro Infuser plus a water building. Water is needed for hydration, housing and terraforming.
2. Food — a Grow Pod or equivalent food building. Rations from crates run out; a Grow Pod does not.
3. Oxygen — a second Oxygen Emitter. The first one keeps you alive; the second one extends your range.
4. Heat — a Thermal Drill. Heat is a terraforming resource, not a survival meter, but it unlocks upgrades and later buildings.

Do not build all four at once. Each one adds power draw and another building to defend. Add water first, then food, then expand the oxygen cluster. The resources guide→ explains which nodes feed each chain.

Expedition checklist

Before you leave the green zone:

• Check oxygen and hydration are full.
• Carry one oxygen supply and one medical item.
• Carry two waters and two rations.
• Note the attack timer. Do not leave with under a minute remaining.
• Mark the route home. The map view shows your base and the terrain you have revealed.
• Empty inventory space for the resources you are targeting.

During the trip:

• Gather the nearest nodes first, then move outward.
• Turn back when oxygen is at one third, not when it is empty.
• Avoid alien nests. They are not resource nodes; they are spawners with defenders.
• Do not engage flying enemies in the open. They are faster than you and they ignore walls.

Surviving Winterbloom

Winterbloom adds cold terrain and heavy enemies. The survival pressure shifts from oxygen alone to heat and defense. Thermal Drills produce Heat, and the region's enemies are designed to break static lines. Keep a fallback Habitat or Teleport Relay powered so you have somewhere to recover.

The Teleport Relay is the key quality-of-life building in the mid-game. Once it is powered and the population target is met, you can leave the region without walking back across the map. Build it early in every region and protect it.

What happens when a meter empties

The game does not publish exact penalties. Treat an empty oxygen or hydration meter as a failure state and avoid testing it. Health reaching zero ends the run or forces a reload; either way, the cost is the time since your last save.

The store page confirms manual saving and Steam Cloud. Save before a long expedition and before calling a wave early. There is no autosave guarantee in the demo.

A simple rule set

• Green is safe, purple is timed.
• Water is for drinking first, building second.
• Food is a production problem, not a scavenging problem.
• Health items are for emergencies, not for topping off.
• Oxygen emitters are defensive objectives; wall them in.
• The Teleport Relay is the best escape hatch in the game.

If you are still learning the build order, the beginner guide→ puts these systems in sequence. If you are dying specifically during waves, the defense guide→ is the better next read.

FAQ

How do I restore oxygen in Project Tomorrow?

Stand in green ground, return to your base, or use a crafted oxygen supply. Oxygen emitters create and expand the green zone.

Can you drink dirty water in Project Tomorrow?

You can, but it damages health. Purify it or find clean water instead.

Do I need food in the demo?

The demo focuses on health, hydration and oxygen, with rations as consumables. Food production becomes a larger system in Tidehaven and the release build.

How do I survive the wasteland?

Go out with full meters, carry an oxygen supply, turn back at one third oxygen, and do not fight away from your turrets.

Sources

• Project Tomorrow on Steam ↗
• Project Tomorrow Steam news: Tidehaven and survival systems ↗
• Project Tomorrow achievements ↗
• Wolfman Mazy demo gameplay ↗

Official source: Project Tomorrow on Steam ↗ Project Tomorrow guides and walkthroughs