Hidden Wonders | Hakusui Dam, One of Japan's Most Stunning Sights

Hakusui Dam graces the verdant mountains of Taketa City, Oita Prefecture. It is often called Japan's most beautiful dam. Cascading waters create scale-like ripples, their rush echoing through lush greenery. Officially named the "Hakusui Reservoir Weir Water Management Facility," it was designated as an Important Cultural Property of Japan in 1999.

*The flowing water looks like a lace curtain fluttering in the wind. (©Sankei by Kan Emori)*

A Feat of Engineering

Beyond its beauty, the dam plays a vital role in supplying crucial water for agriculture to fields and rice paddies. Taketa City boasts numerous historic water management facilities, such as reservoirs and circular aqueducts, showcasing ancestral wisdom in infrastructure.

Built in 1938 to alleviate agricultural water shortages, Hakusui Dam features a unique design with a smooth, curved right bank and a stepped left bank, engineered to disperse water pressure in delicate geological conditions. Nearly 90 years later, its water retention capacity and elegant curve stand as a testament to past engineering prowess. According to Shigehiro Okabe, the district office director overseeing the dam, "It is said that the curve was constructed using stacked tuff stone that was excavated during the construction of the left bank."

Supporting Livelihood Through Water

Another notable water management facility is the Otonashiiro Circular Diversion No 12. Constructed in 1934, the structure distributes water from the Otonashiiro irrigation canal to three locations.

*Water flows steadily from Otonashiiro Circular Diversion No 12, supporting local agriculture. Taketa City, Oita Prefecture. (©Sankei by Kan Emori)*

Water continuously flows from 20 "water windows" in a 6.4-meter diameter cylinder, feeding into three separate channels. It effectively resolved local water disputes and, although converted to concrete in 1984, maintains its original structural integrity. The plaque commemorating the aqueduct bears the poignant inscription: "Water is the soul of farmers."

The Wakamiyairo Sasamuta Aqueduct, with its two arches covered with ivy, is another sight to behold. Overlooking the iron bridge of the Hohi Main Line, the aqueduct bridge spans 59 meters (194 ft) in length and 4 meters (13 ft) in width, carrying water from the Wakamiyairo aqueduct. The bridge was completed in 1916 but collapsed shortly thereafter. It was promptly rebuilt the following year.

*The Wakamiyairo Sasamuta Aqueduct covered in ivy. (©Sankei by Kan Emori)*

The modernization of local agriculture has led to increased crop yields, made possible through the tireless service of numerous water management facilities in Taketa. Today, these facilities continue to uphold the enduring wisdom and perseverance of earlier generations.