This dive site, the Nagaragawa River in Japan, is celebrated as one of the nation's three major clear streams, offering exceptional underwater clarity. While typical depths range from 3 to 6 meters, some sections can reach over 10 meters, providing varied diving experiences. As a river environment, underwater navigation generally involves following the natural flow, though specific entry and exit points would dictate a planned drift or shore dive.
The river teems with diverse freshwater aquatic life. Divers can expect to encounter rainbow trout and rockfish in the upper reaches, while the middle sections are abundant with ayu and catfish. Additionally, the Nagaragawa is home to rare species such as the unique stone-like Ayu salmon and sea trout, alongside intriguing creatures like the Japanese Green Turtle and Mokuzu crab.
The high clarity is a significant highlight, making it suitable for both diving and snorkeling. The best time to visit would typically be during drier seasons when water levels are stable and currents are more predictable. Divers should be prepared for potentially cooler freshwater temperatures and variable currents characteristic of a river system. It's an excellent destination for observing unique freshwater ecosystems and macro life.
