is a Japanese manga series written and illustrated by Rettà  Tajima. It was serialized in Kodansha's shà Ânen manga magazine Bessatsu Shà Ânen Magazine from August 2018 to July 2020, with its chapters collected in three volumes. A live-action film adaptation premiered in June 2023.
Written and illustrated by Rettà  Tajima, Mizu wa Umi ni Mukatte Nagareru was serialized in Kodansha's shà Ânen manga magazine Bessatsu Shà Ânen Magazine from August 9, 2018, to July 9, 2020. Kodansha collected its chapters in three volumes, released from May 9, 2019, to September 9, 2020.
In November 2022, it was announced that the manga would receive a live-action film adaptation. It is directed by Tetsu Maeda with scripts written by Satomi Oshima, and stars Suzu Hirose as Chisa Sasaki. It premiered on June 9, 2023.
The manga ranked 18th on the 2020 "Book of the Year" list by Da Vinci magazine. On Takarajimasha's Kono Manga ga Sugoi! ranking of top 20 manga for male readers, the series ranked fifth on the 2019 list, and fourth on the 2020 list. The manga was nominated for the 13th and 14th Manga Taishà  in 2020 and 2021, respectively. It won the 24th Tezuka Osamu Cultural Prize's New Creator Prize in 2020.