Takayama Dam (高山ダム)
Takayama Dam is located a short distance upstream from the confluence point of the Yodo-gawa River System stretch of the Kizu-gawa River and its arm Nabari-gawa River in Oaza Takao, Minami Yamashiro-mura, Soraku-gun, Kyoto Prefecture. It is one of several dams in the upstream area of the Kizu-gawa River.
The Yodo-gawa River contributes a great deal to Kansai's political and economic activities as one of the main transportation methods in the Kinki region. However, it has flooded a number of times over the centuries. In an attempt to prevent such floods, various measures have been implemented since the Meiji period such as building Setagawa-araizeki Barrage, the drainage of Oguraike Lake and its isolation from the Uji-gawa River, and the Shin-Yodogawa-kaisaku (new project of cutting the river wider). In 1953, the 13th typhoon of the year hit Yodo-gawa area, causing huge damage in spite of these river improvement works.
Because the floods caused great damage that year, and in fear of further deterioration in the state of Japan's fragile economy that had been decimated by losing the War, the Economic Stabilization Agency tried to prevent increasing flood damage by working out a comprehensive plan for the development of ten main river systems including the Yodo-gawa River, the Tone-gawa River, the Kitakami-gawa River, the Kiso-gawa River, the Yoshino-gawa River, and the Chikugo-gawa River. The 'Revised River Improvement Plan' including the building of multipurpose damswas published in 1949, and for Yodo-gawa River system, the 'Revised Basic Plan for Improvement of Yodo-gawa River System' was fixed in 1954. In accordance with this plan, the Construction Ministry Kinki Regional Construction Bureau (the current Ministry of Land, Infrastructure and Transport Kinki Regional Development Bureau) implemented measures of flood control based on the amount of flood water caused by Typhoon 13. For the main stream of the Yodogawa-River, it worked out a plan to build Amagase Dam in addition to dredging the Seta-gawa River, and strengthening dikes such as repairing Setagawa-araizeki Barrage.
For Kizu-gawa area, it considered development of the tributary area of the Kizu-gawa River, because there were no appropriate places to build dams on the main stream of the river. Selecting the Nabari-gawa River from a short list, the Construction Ministry made a plan to build Tsukigase Dam over the main stream of the Nabari-gawa River and Udagawa Dam (later Muro Dam) over the Uda-gawa River, and started a preliminary study of these sites as the 'Comprehensive Development of the Upstream Area of Kizu-gawa River' in 1952.
Development until completion
Although, in 1958, they began the study of the implementation of the plan to roughly design specific types of dams and their capacities of water, they had to review the original flood control plan because the Ise Bay Typhoon in the following year (1959) brought about considerable flooding, surpassing that of Typhoon 13, and furthermore, water demand grew tremendously due to the rapid growth of the population in the Kansai area and the expanding Hanshin Industrial Zone. Growing calls for the development of water resources resulted in putting 'Water Resources Development Promotion Law' into effect in 1962.
After the Tone-gawa and Yodo-gawa River systems were designated for water resources development based on the 'Water Resources Development Basic Plan,' their comprehensive management around utilization was transferred to Water Resources Development Public Corporation (now Japan Water agency), including the operation of Takayama Dam (former Tsukigase Dam) and Udagawa Dam. Because the area to be submerged under water straddled the three prefectures of Kyoto, Nara, and Mie having 196 households, and part of Tsukigase plum-grove park that was designated as national scenic beauty was also to go under water, the negotiations on compensation went through extreme difficulties. After many twists and turns, Takayama Dam was completed in 1969, 17 years after the start of the preliminary study.
Those having a key role in the group of Kizugawa Dams
Although its name was initially Tsukigase Dam, following the former residents' hope that the name of their submerged Takayama village should be kept alive, its name was changed to Takayama Dam. It was initially planned to be a concrete gravity dam with the same appearance of that of Sonohara Dam (Katashina-gawa River), but later it was changed to a gravity arch dam to reduce construction costs, because it turned out that the place had a relatively hard rock ground. It is a large scale gravity arch dam of 67.0 meters in height, with Nanairo Dam (Kitayama-gawa River) being the only other of the same type in Kinki region.
The objectives of this multipurpose dam are: (1) flood control of the Kizu-gawa and Yodo-gawa areas; (2) the common purpose of dams in Japan (supply of water for agriculture that is the vested right of the farmlands in Kizu-gawa area); (3) the supply of drinking water to densely-populated areas such as Osaka City, Hirakata City, Moriguchi City (Osaka Prefecture): and Kobe City, Nishinomiya City, and Amagasaki City (Hyogo Prefecture); (4) hydroelectric power generation by the Kansai Electric Power Co., Inc. (permitted output: 6,000 kW). Managed by Kizugawa Dam Integrated Operation & Management Office, it plays a key role within the group of dams in the Kizu-gawa River System as the first dam over Nabari-gawa River.
Later, Shorenji Dam (1970), Muro Dam (1973), Nunome Dam (1991), and Hinachi Dam (1998) were completed to make important water resources for the Kansai area. Kawakami Dam is under construction at the Maefukase-gawa River, a subsidiary stream on the left of the Kizu-gawa River, while Yodogawa River System Committee's recommendations in 2005 led to the conclusion that "it is appropriate to abort the construction," and the agency's supervisory Ministry of Land, Infrastructure, Transport and Tourism intends to change the dam to a flood-control dam, but Mie Prefecture, Iga City, residents in the river area, and those residents to move out oppose the Ministry's intention saying that the construction should be continued as it is planned.
The lake was named Lake Tsukigase, which came from the Tsukigase plum-grove park, a scenic spot by the lakeside. Every spring more than ten thousand plum trees are in bloom in this park, where many tourists from the Kansai and Nagoya regions enjoy their spring scent and the scenery. In addition to Tsukigase Onsen (hot spring), which is close to the plum-grove park, Iga Ueno-jo Castle, a ninja house, and the valley of Mt. Kasagi where Emperor Godaigo secretly visited, are nearby, and if you go a little farther you can see Hase-dera Temple, Muro-ji Temple, Akame Shijuhachi-taki Falls, and Kochi-dani Valley. Using a car is recommended to reach the dam, because National Route 25 and Meihan National Route run close by, and it takes about 90 minutes to get there from the center of either Osaka City or Kyoto City.