"As I was tossed around, flipped, and pummeled like laundry on a heavy-duty cycle, my control crumbled. I was a scared kid again, screaming for the big bad world to leave me alone. My rage exploded. And so did the river. It blasted away from me in every direction, putting me at ground zero of the detonation -- curled up alone in a bubble of air, howling so loudly I could hear myself even over the roar of the torrent. Some part of me had reached outward . . . not just into the pool, but to the source of the river, deep down in the Underworld or maybe Yonkers, and I had pulled it up by its roots. Millions of metric tons of water roared through the cavern, flooding the pool, scouring the cliffs, surging over the riverbanks, and probably surprising a whole bunch of snakes bathing downstream. At last, the water crashed back around me, settling into its normal flow again." (Chalice of The Gods).

Basically rapidly moves millions of metric tons of water into a cavern, possibly pulling it up from the Underworld.

Calc: https://vsbattles.fandom.com/wiki/User_blog:GraveDigger84/Percy_nukes_the_Elisson

Hope the verse gets better feats in The Wrath of The Triple Goddess but I honestly doubt it.