Acoording to Hindu myths..

NORTH REPRESENTS BIRTH......
North is the side which lies on the sun’s right hand and lies on either side of life; it
symbolizes night sky and night wind and is the home of the Moon and the Milky
Way. North represents coldness, alienation, and hostility; it is the abode of death
SOUTH REPRESENTS DEATH
South is the side which lies on the Sun’s left hand and is the hand of fire.

According to hindu mythology the person's good/bad deeds while on earth and decides if the soul goes to a heaven and/or a hell, for how long, and in what capacity. Some versions of the theology state that good and bad deeds neutralize each other and the soul therefore is born in either a heaven or a hell, but not both, whereas according to another school of thought, the good and bad deeds don't cancel out each other. In either case, the soul acquires a body as appropriate to the worlds it enters. At the end of the soul's time in those worlds, it returns to the earth (is reborn as a life form on the earth). It is considered that only from the earth, and only after a human life, can the soul reach supreme salvation, the state free from the cycle of birth and death, a state of absolute and eternal bliss.

Varanasi, which stands on the West bank of the River Ganga in India, is often called the City of Death. In the Hindu faith, it is said to be the most auspicious place to die and have one’s remains submersed in the river. Moksha, or liberation from the cycle of life and death, is believed to be the grace of the water itself.

The virtuous Varanasi on the banks of Ganges is one of the most important pilgrimages for Hindus and Buddhists. AT VARANASI THE RIVER GANGA FLOWS FROM SOUTH TO NORTH ie. back towards its origin in the Himalayas, considered a most auspicious phenomenon by Hindus. Varanasi has been the center of education, religion, art of culture since ages. Varanasi indeed offers the incredible India at its religious and cultural zenith.

So the direction of flow of the holy River Ganga  symbolises the path of .....Death to Life

GANGA THE MIGHTY RIVER OF INDIA