Water on Mars

I just thought I'd bring up the discovery that Mars' northern pole has between 2 - 3 million cubic kilometres of ice (about 95% pure). This is about 100 times the volume of North America's Great Lakes. On Earth there are about 41 million cubic kilometres of freshwater. About 69% is thought to be locked into permanent ice and snow. About 30% is located within soil and aquifers. This leaves about 1% or 0.41 million cubic kilometres to run free on the surface. A large number of people get drinking water from aquifers, but this suggests that with wise management, Mars' water should be able to support a population substantially larger than what now exists on Earth.