Wet Mars Mon. I m just home from Hawaii and the West Coast Science Fiction Convention. Ctein has a lot to say about Mars and water.
Any underground water is kept liquid by overlying pressure and Mars s internal heat.
Where there are openings to the surface, they re plugged with ice. Growing pressure or tectonic action might cause water to burst through into the near-vacuum. Then we get to guess how far it can run downhill while simultaneously boiling and freezing. Notice that nobody has actually seen water. Life has been found everywhere on Earth that we find water.