liquid

Liquid production and handling determines how long an island can keep growing. Water is needed for settlements, farms, power, and rockets, while poor liquid management can create pollution, disease, and waste.

Water sources

Groundwater

Groundwater is the main inland source of fresh water. It is extracted with a groundwater_pump or groundwater_well, and the deposit is replenished by rain.

Groundwater reserves are finite, so they must be managed carefully. Rainfall slowly restores them, and regeneration scales with reservoir size and rain intensity. Consistent rain makes groundwater much more sustainable than dry climates.

Ocean and rainfall

When groundwater is not enough, water can be gathered from the sea or directly from rain.

seawater_pump pumps water from the ocean and must be built within a limited height above sea level.
seawater_pump_tall works higher above sea level, but uses more power.
rainwater_harvester collects rainwater during rain and stores a small amount in an internal tank.

These sources are useful early, but they are usually not enough for large-scale demand on their own.

Water recycling and desalination

Several buildings convert lower-quality water into usable fresh water:

wastewater_treatment turns dirty water into clean water.
thermal_desalinator heats salt water into steam and collects fresh water, producing brine as a byproduct.
basic_desalination lets a basic distiller be repurposed for desalination.
vacuum_desalination enables desalination using exhausted steam.

These technologies become more important as freshwater reserves tighten.

Water for settlements and farms

Settlement supply

water_facility supplies attached settlements with fresh water and returns wastewater that must be disposed of. Supplying fresh water increases Unity and reduces health risks.

Clean water is not optional for stable growth. A settlement with a reliable water supply is healthier, more productive, and easier to manage.

Farming

irrigated_farm can be connected to a water source or fertilizer source. This allows crops to be supported beyond natural rainfall alone.

Water-saving and yield-improving effects also matter:

water_saver reduces water consumption in settlements and farms.
rainwater_yield increases rainwater collection.
farming_boost increases farm output but also increases water demand.

These modifiers can make the difference between self-sufficiency and a persistent water shortage.

Water pollution and health

Pollution risks

Some liquid handling creates water pollution, and polluted water directly harms health and happiness. Water pollution is especially dangerous because it is stronger per unit than air or vehicle pollution.

Disease

cholera spreads through contaminated water. The cure is prevention: keep a stable supply of clean water and avoid letting polluted water enter the settlement system.

Waste handling

Liquid waste must be handled deliberately.

liquid_dump disposes of liquids into the ocean, but some liquids pollute the water.
wastewater_treatment is the standard way to recover useful water from waste streams.
sour_water_stripper makes sour water useful by extracting ammonia and sulfur.

Good wastewater treatment eliminates one of the biggest long-term threats to settlement health.

Liquid transport

Pipes and flow control

pipe transports liquids and gases, but each segment can carry only one product type at a time. That makes dedicated routing important.

Flow management tools improve reliability:

pipe_connector connects multiple pipes and distributes products between them.
pipe_balancer distributes liquids and gases between connected pipes with priority support.
pipes_ii increases throughput by using a larger pipe diameter.
pipes_iii provides even greater liquid transport capacity.

When designing a liquid network, separate incompatible products early and use balancing only where flow needs to be stabilized.

Tank and wagon transport

Liquids can also be moved by vehicle:

haul_truck_tank is a large hauling truck that transports only liquid or gas products.
tanker_wagon transports fluid materials by rail.
fluid_station_module handles loading and unloading of liquid cargo wagons.

Vehicle transport is useful for long-distance logistics or when pipe routing is impractical.

Industrial liquid processing

Chemical and fuel processing

Several industrial buildings work directly with liquids:

chemical_plant performs chemical recipes, including fluid processing and packaging.
liquid_fuel_module refuels locomotives and tenders with liquid fuel.
water_saver and other production modifiers can reduce operating pressure on the water system.

Oil and fuel chain

Liquid production is not limited to water.

oil_pump extracts crude oil from underground.
basic_diesel enables pumping the island’s limited oil reserves and converting them to diesel.
basic_distiller can distill low-quality diesel, but it is inefficient and produces a lot of waste.
distillation_stage_i is the first step of advanced crude oil processing.
cracking_unit transforms petroleum products to rebalance consumption.

These buildings are essential for fuel autonomy and for turning crude resources into usable products.

Power and cooling

Water is tightly linked to power generation and heat management.

cooling_tower improves a power plant’s water efficiency by recovering steam back into water.
boiler boils water to produce high-pressure steam by burning fuel.
cooled_caster casts molten materials into slabs and also uses water for cooling.

These systems help close the loop between water consumption and heat recovery.

Salt and brine processing

Salt water can be turned into useful products rather than wasted.

evaporation_pond produces salt by evaporating remaining water from brine.
evaporation_pond_heated speeds up the same process with electric heaters.
thermal_desalinator and vacuum_desalination also create brine as part of freshwater production.

Brine handling is a useful late-game source of salt and a sign of a mature water infrastructure.

Disposal and special liquid systems

Ocean dumping

liquid_dump is a final disposal option for excess liquid, but it should be used carefully because it can pollute surrounding water.

Rocket launch water use

The rocket_launch_pad must be connected to water because rocket launch requires a large amount of it to dampen exhaust shock waves. It also needs the correct fuel connection for the rocket type, and fuel is never stored on the pad itself for safety.

Strategic notes

Water scarcity is one of the main limiting factors in the game. Groundwater is valuable but finite, rainfall is inconsistent, and ocean water must be treated before it can support settlement growth.

A strong liquid strategy usually follows this order:

Secure early fresh water from groundwater, rain, or the sea.
Build wastewater treatment before pollution becomes a health problem.
Expand into desalination for long-term independence.
Use pipes, balancers, and tank transport to keep liquids moving efficiently.
Recover steam, recycle brine, and reduce consumption wherever possible.

Settlements that master liquid management can support larger populations, healthier workers, and more advanced industry without collapsing under their own waste.