[3] The plant is a perennial rhizomatous herb producing narrow, compressed, unspotted stems, up to a length of about 1 m,[3][4] which are unbranched or sparingly branched.

[5] It has two types of leaf: The inflorescence is a small spike of flowers that arises from the water on a peduncle 1.5–5 (rarely, up to 16) cm.

[3][7] Potamogeton epihydrus (meaning 'on the water surface') was described by Rafinesque in 1808,[1] one of the earlier North American species to be named.

DNA analysis[8] indicates that, despite the presence of floating leaves, P. epihydrus is closely related to P. tennesseensis, both of which are within the basal members of the large clade of fine-leaved pondweeds including P. diversifolius, P. pusillus and P. compressus.

Its centres of distribution are the northeastern US; southeastern Canada, from the Atlantic to the Great Lakes; and the Pacific seaboard from northern California to British Columbia.