Water

Types
In ECO there is fresh water and salt water. The effects on e.g. farming is yet widely unknown and remains to be tested.

Physics
It is impossible for the player to "shoot", e.g. mine, at blocks when submerged, while the ability to place blocks remains.

Blocks (only tested with dirt and stone) cannot be placed directly in a stream of water, while stone can be placed indirectly in the stream, by letting it drop from above (see stone).