The flows through Kumamoto, Ōita, Fukuoka and Saga prefectures in Japan. With a total length of , it is the longest river on Kyūshū. It flows from Mount Aso and empties into the Ariake Sea. It is also nicknamed "Chikushijirō". The upper reaches of the river are important to forestry, and the middle and lower reaches are important to local agriculture, providing irrigation to some of rice fields on the Tsukushi Plain. The river is also important to industry, with twenty electrical power plants located along its banks, as well as the major city of Kurume in Fukuoka Prefecture. Recognizing the requirement to satisfy divergent needs of various communities along the river, the Japanese Ministry of Land, Infrastructure, Transport and Tourism designated the Chikugo River (along with six other river systems in Japan) as a "Water Resources Development River System" with a comprehensive utilization plan to develop the river's resources. The Chikugogawa Onsen Fireworks, held annually on July 28, are the largest fireworks display in Kyūshū. The event has been held since 1650 on the riverbanks at Kurume. See also Chikugo River Lift Bridge References de Graaf, Rutger. Urban Water in Japan. CRC Press (2008). Japan Water Agency map Chikugogawa Onsen Fireworks Notes Rivers of Fukuoka Prefecture Rivers of Kumamoto Prefecture Rivers of Ōita Prefecture Rivers of Saga Prefecture Kyushu region Rivers of Japan