This paper considers the ways in which William Blake’s The Four Zoas portrays and embodies water. It argues that the poem’s focus on water through the figure of Tharmas, a water deity invented by Blake, contributed to the poem being left in manuscript form. The article explores how water seeped into the format of the text and into its aquarelle images, making them too unruly for printing in Blake’s usual etching method. The central motif of the flood affects the manuscript’s outlines, which become porous, and run the risk of disintegrating altogether. Yet water is also shown to allow a rebirth for the poem, giving it fluid, dynamic, and lasting energy.