The river is a man-made canal excavated in 1610 by order of Fukushima Masanori to allow ships to bring goods to the city.

In modern times, pollution has slowly damaged the water quality until the 1960s, where it peaked.

Recently, citizens began collecting signatures to initiate the Horikawa River 1000-Citizen Survey Network.

With the help of these volunteers, the Nagoya City Council carried out experiments aimed at clarification of the river.

[1] Media related to Hori River (Nagoya) at Wikimedia Commons