Shinano River

The Shinano River's flow and environment are vital, supporting the life and products of the vast areas within Niigata and Nagano Prefectures. The river supplies essential water for hydropower generation, irrigation for agriculture, industrial uses, and municipal water plants, underscoring its crucial role in regional development and daily life.

The Shinano River is located in Japan on the island of Honshu. It originates in the Japanese Alps and flows through the Nagano and Niigata prefectures, eventually emptying into the Sea of Japan. Its upper reaches are known as the Chikuma River.

At the Asahi Bridge, located 34.5 km from the river mouth, which serves as the official stream gauging location, the water surface width of the Shinano River is approximately 140 meters. The maximum depth recorded in the downstream part of the bridge was 9.37 meters.

The Shinano-gawa is recognized as the longest river in Japan, stretching 367 km. It originates in the high mountainous region of central Honshu Island, often referred to as the Japanese Alps. Its abundant waters flow towards the Echigo Plain, fostering extensive and rich rice paddy fields.

The water from the Shinano River is crucial for multiple purposes, including generating hydropower, irrigating agricultural lands, supporting industrial activities, and supplying city water treatment plants. This multifaceted usage highlights the river's significance to the economy and well-being of the surrounding regions.