Lake

A body of fresh water with almost no current. In summer it separates into a warm top layer and a cold bottom layer that do not mix. The cold, dark bottom of a deep lake preserves wrecks, bodies and structures in the condition they sank in.

Regional environment Aquatic (water)

Tropical Dry Temperate Continental Polar

Lowland Highland

Crossing it

Navigate: DC 8
Forage: DC 8
Notice: DC 10

The water is flat, and a crossing is short and entirely exposed.

In play

Exposed crossing

A vessel on open lake water has no cover and is visible from every shore. Encounter distance is Long.
Thermocline

Below the summer thermocline the water is near freezing and sonar does not cross it cleanly. A creature below it is hidden from anything above.
Preservation

Cold fresh water preserves what sinks in it. Anything recovered from a deep lake bottom is in the condition it sank in, regardless of how long ago that was.

Variations

Shallow lake

Mixed top to bottom, warm and productive. Weed beds are difficult terrain for swimmers.
Rift lake

Hundreds of feet deep and old, with endemic species and an unsurveyed bottom.
Subglacial lake

Under an ice sheet and sealed off from the surface. Reached by bore.

Worlds it occurs on

Terran (Arctic) A rocky world covered in ice for most of the year but habitable, with open water at the margin in summer.
Terran (Verdant) A rocky world with liquid water, breathable air and a magnetic field to protect them, rare and the cause of most wars.