Preah Mae Kongkea
The Ganges is the sacred river of many religions in India, especially the Hindus. As the Ganges does not flow through Cambodia, the Tonle Sap river has been considered the local sacred river. Though it is not a seafaring river, it is an important source of water for raising livestock and provides Cambodia with an abundance of silt and fish stocks.
In Hindu mythology, Preah Mae Kongkea is personified as a young woman wringing the cool waters of detachment out of her hair to drown Mara, the demon sent to tempt Gautama Buddha as he meditated under the Bodhi Tree. In a similar way, the reversal of the Tonle Sap will provide the fishers and farmers with fresh water, food, and life.
Making a small offering of bratip as a grateful sacrifice to the Preah Mae Kongkea is seen a good omen for happiness and fishing as a daily livelihood on the Tonle Sap.
Makara and Dragon boat races
Another popular Hindu legend concerns the theomachy of Makara and the goddess Ganga. This battle followed the accidental fall of one hair of the Ganges goddess, or "Kong Kea" in khmer. Her hair fell down from paradise to the center of the earth made the sea dragon or water-monster Makara or Makor in khmer, more powerful than any other animals in the world.
Makor swallowed all the other animals and therefore the humans begged goddess Kong Kea for help, that she would come down to earth and take control over Makor again. Makor start swallowing the seven-headed dragon Mucalinda but did not succeed. Goddess Kong Kea asked Shiva, or Eyso in Khmer, to catch Makor in return of which she would marry him.
Eyso came down to the earth and starter a battle with Makor. After three days of fighting, the battle was a tie. Kong Kea then hid the hand of Eyso using her hair to dry up the water. Makor, growing tired, and surrendered to Eyso, who used Makor as his vehicle to ride to goddess Kong Kea and marry her.
Makor changed names to "Koch Jor Sey" which is related to "Reach Sey", the King Lion, protector of Kingdom of Cambodia. The dragon boat races can be seen as a reenactment of these mythological battles.
On the second day of the Royal Water Festival, a special commemoration of Lord Indra is celebrated. The reversal of the Tonle Sap suggests why a parallel could be drawn by the Khmer people with Lord Indra. Indra is the one who releases the water from the winter demon.
This is the most common theme of the Rigveda concerning Lord Indra: he as the god with thunderbolt kills the evil serpent Vritra that held back rains, and thus released rains and land nourishing rivers. For example, the Rigvedic hymn 1.32 dedicated to Indra reads:
Let me tell you the manly deeds of Indra, which he first accomplished, bolt-weaponed,
He slew the serpent, opened up waters, cleft in twain the belly of mountains,
He slew the serpent on the mountain, with heavenly bolt made by Tvastar,
Like lowing cattle downward sped the waters, then flowed to the ocean.
King Barom Reachea I also known as Bormin Reachea in the year (1568 AD) is said to have seen in the dream the place of this battle between Indra in Vritra as the Tonle Sap River in front of the Royal Palace.