Water

Water is a fluid block that can be a barrier to travel or a useful resource.

Water

Where Found

Water occurs naturally on the surface of a generated world in the form of ponds, lakes, and oceans. It can also spawn underground.

Flowing

It's possible for water to flow from one block to another, either when an adjacent block is removed, a block is added in space occupied by water, or when a bucket of water is emptied. Water will seek to fill the lowest available space but will not decrease in volume doing so, which can result in spaces being partially filled with water.

Water will flow over drop-offs and "splash" across the top of blocks. This can cause unexpected problems as water will dislodge placed items such as ladders or oil lanterns, dropping them for pick-up by the next Blockhead that passes them. Other placed items such as steel lanterns are unaffected.

Whether water will flow between two adjacent partially filled blocks appears to be determined by comparing their relative levels. If there is insufficient difference, there will be no flow. This can result in a very gentle, descending gradient across long expanses. (In one test, there was a drop of 28 pixels over a span of some 93 blocks with 80-pixel blocks after the water settled.) A significant difference in water height will cause "splash" particles to be produced as the water flows.

When multiple water blocks are directly over air blocks, there may be a flickering pattern of air and water as the two trade places.

Freezing

Free-standing water in an area experiencing sufficient cold (such as falling snow) may freeze into ice if the water level is high enough. Trace water may disappear. Under warmer conditions, ice may melt into water.

Water close enough to cold air will freeze into ice, the distance dependent on the degree of cold. Conversely, ice close enough to warm air will melt.

Evaporation

If standing water is low enough in a block space, it may "evaporate" and despawn. This seems to happen mostly when no more than one adjacent block contains water, resulting in the visual effect of retreating water as a series of low water blocks despawn.

Harvesting

It's not possible to pick up water directly.

Using a bucket on water will change the bucket into a bucket of water. This can be done on even partially filled spaces if the water level is high enough. The minimum level of water that can be picked up in a bucket is believed to be 20% (one fifth) of a block.

Drowning

A Blockhead who has its head fully immersed in water will suffer from a lack of air and begin reducing their air bar.

Uses

Water cannot be used directly for crafting, but is needed for some crafting recipes in the form of a bucket of water.

Kelp cannot be planted in a block that isn't under sufficient water.

Notes

Free-standing water that's close enough to magma or another source of heat (such as a campfire) will begin boiling, giving off puffs of steam.

Due to some quirks of how it's implemented, it's possible to generate water in two ways:

Water that partially fills a space will freeze into a full block of ice, which can then melt into a full block of water.
Causing water to spill into two or more open blocks may allow each partially filled space to be picked up by a bucket, which when emptied will produce a full block of water.

Gallery

Water boils near magma
Water draining down an irregular vertical shaft, note the flowing accumulation at the bottom