The Planetary Veins are major underground rivers which circle the planet and make Alphaworld a hospitable planet. These rivers move erratically throughout the world caused mostly by Alphaworld's three moons, and other minor factors such as geothermal and volcanic activity.
In Alphaworld, most colonized areas are based along these veins as they provide a number of necessities. They provide drinking water, water for crops and livestock, and hydro-power.
Long ago, the Imperial Sewers used the planetary veins as the final destination for the waste and sewage they carried.
A radar image of the planetary veins can be seen using this satellite picture of Alphaworld.
Planetary Vein Map