The dam is constructed with a multi-purpose design to manage flood control, water supply, and hydroelectric power generation.
The reservoir, Miyagase Lake, covers an area of approximately 4.6 square kilometers when filled to capacity.
It is one of the largest concrete gravity dams in the Kanto region of Japan.
The dam's discharge events are scheduled periodically, attracting significant interest for the volume of water released.
Construction required the relocation of several settlements, and historical markers commemorate these former villages.
The dam features an internal inspection gallery and a visitor center detailing its engineering and environmental impact.
Miyagase Dam is a massive concrete gravity dam completed in 2000, standing 156 meters tall within the Tanzawa-Oyama Quasi-National Park. The structure regulates the flow of the Nakatsu River and provides water supply and flood control for the Kanagawa Prefecture. It features a prominent water discharge system that creates a dramatic visual effect during scheduled release events. Visitors can access the dam crest via an inclined plane cable car or by walking up a dedicated trail. The surrounding Miyagase Lake serves as a major reservoir and recreational area for boating and hiking. The dam contains a hydroelectric power plant integrated into its base structure. It is located in the Aiko District, approximately 50 kilometers southwest of central Tokyo.
The viewing platform at the base of the dam for the full scale of the discharge; the crest for a panoramic view of the reservoir.
Use the inclined plane cable car if you prefer to avoid the steep hike from the base to the crest.
Check the dam's official website for the discharge schedule to ensure your visit aligns with an event.
Explore the surrounding lakeside parks, as they offer extensive trails that provide different perspectives of the dam structure.
Attempting to climb the dam wall outside of designated stairs or the cable car route; failing to check the dam's discharge calendar.
The dam visitor center typically closes during the year-end and new-year holidays.
Maintain caution near water intake zones; adhere to safety barriers and restricted area signage.
