Water rush rhizome is robust, with many adventitious roots. The stem is tall and cylindrical, with the uppermost leaf sheath bearing a blade. The leaf blade is linear. There is one bract, elongating the stem,直立, lanceolate, usually shorter than the inflorescence, rarely slightly longer. The lateral panicle is simple or compound, pseudolateral; spikelets are solitary or in 2-3 clusters at the tips of the radiating branches, ovate or oblong, with an acute or obtuse apex, bearing many flowers; lemma elliptic or broadly ovate, slightly concave at the tip, with a short awn, membranous; stamens 3, anthers linear, the anther tube prominent; style of moderate length, stigma 2, rarely 3, longer than the style. Achenes are obovate or elliptic, biconvex, rarely trilobed, about 2 mm long. Flowering and fruiting period is from June to September.

Produced in multiple provinces across China; grows along lake shores or in shallow ponds. Also found in Korea, Japan, Australia, and North and South America. Cultivated in Beijing for ornamental purposes; commonly used in Yunnan and surrounding areas to make bamboo mats.