This newly-discovered ice field is half-way between the north pole and the equator. It contains as much water as Lake Superior, and covers an area the size of New Mexico. It is between one and ten meters below the surface - very easy to reach by drilling or excavation by future Mars colonists.
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PROBLEM: Mars settlements need ready access to water and energy. Hydrogen can be extracted from water and combined with atmospheric carbon dioxide and electricity to create methane and oxygen rocket propellant for return flights to Earth. This process is absolutely critical for any mars mission, because a flight that takes all its own fuel to Mars will weigh for times as much and cost ten times more than one that makes propellant on the surface.
Locating a base near the equator dramatically increases the amount of sunlight available year-round, which can be converted to electricity. It also is easier to reach orbit and arrive from an equatorial orbit, as well as return to Earth. The two moons of Mars orbit directly over the equator, and are much more accessible from the equator than the poles. The problem is that any water ice at the equator is either deep underground, or takes the form of frozen "mud" and clay materials. In either case, this relatively-abundant advantage in electrical power and heat is partially offset by the far-greater energy cost to extract water from the surface.
The paradox of water-but-low-light versus light-but-little-water is not binary. Every latitude between the pole and equator has a sliding scale of water accessibility versus solar power accessibility.
OPPORTUNITY: Having ready access to water halfway between the north pole and the equator has a number of advantages. It’s deep enough to be stable at latitudes that do not experience months-long seasonal darkness or dry-ice icecap expansion, but shallow enough to be easily accessed. The top layers of surface material (down to roughly 4-5 meters) are considered too irradiated to possibly have native life. Since the icesheet is one to ten meters down, some parts of the deposit are shallow enough to be considered sterile. Mining equipment would be robotic and sterilized anyway, so the risk of forward or back contamination would be minimal.
As an added bonus for these settlers, we have already landed a probe right in the middle of this location. This is the landing site of Viking 2. We have direct soil samples and photos, and an item of historic interest from the highly-successful lander in the 1970's