Omi Taro - Oumi Taro

...The river originates at Mt. Gozaisho (1,210m) in the Suzuka Mountains, flows westward, joins with tributaries such as the Tamura River and the Soma River in Koga County, passes through a narrow area near Ishibe Town in Koga County, and forms a vast alluvial plain in the downstream area of ​​Moriyama City and Yasu County before flowing into Lake Biwa. The upper reaches are made of easily weathered granite and the soft strata of the Kobiwako Group, so it has poor water retention and has been a rough river that has flooded repeatedly every time there was heavy rain since ancient times, and was called ``Omi Taro.'' Downstream from Ritto Town in Kurita County, the river has become a canalized river. ...

*Some of the terminology that refers to "Omi Taro" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…鈴鹿山脈の御在所（ございしよ）山(1210m)に源を発して西流し，甲賀郡で田村川，杣（そま）川などの支流を合わせ，甲賀郡石部町付近の狭隘（きようあい）部を経て，下流部の守山市，野洲郡一帯に広大な沖積平野を形成して琵琶湖に注ぐ。上流部は風化しやすい花コウ岩や軟弱な古琵琶湖層群の地層からなるため，保水性が乏しく，古来，豪雨のたびに洪水を繰り返してきた荒れ川で，〈近江太郎〉と呼ばれていた。栗太（くりた）郡栗東（りつとう）町より下流部では天井川化が著しい。…

※「近江太郎」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報