◇ Establishment of the Development Research Section in the Kitakami River Dam Integrated Management Office The
Tohoku Regional Development Bureau has jurisdiction over the Kitakami River Dam Integrated Management Office related to the "Kitakami River Upstream Dam Restoration Project" to improve the flood control safety of Morioka City. strengthened the system of With the aim of starting early construction of raising the height of the dam body of the Shijushida Dam (Ueda, Morioka City), which will be a key project for flood control in the Kitakami River basin, a specialized department will be established to steadily proceed with research and design. The office will decide on 10 contractors, including the "Yoshida Dam restoration environmental impact assessment business."
Completed image of raising the embankment (provided by the Kitakami River Dam Integrated Management Office)
The Yosishida Dam was completed in 1968 as a gravity-type concrete-fill composite structure. By raising the height of the embankment by 2 meters, the effective water storage capacity was increased from 35.5 million cubic meters to 43 million cubic meters. Increase flood control capacity by about 20%. The rules for operating the Gosho Dam will also be changed, which will be useful for flood control of the Kitakami River, a first-class river that flows through central Iwate Prefecture from north to south.
The newly established Development Research Division will be in charge of dam restoration project planning, project management, budget execution, research, design, and examination work. The Tohoku Development Bureau has appropriated 490 million yen as a related budget for fiscal 2023. In the first quarter (April-June) of this fiscal year, the contractor will be decided ▽ Environmental impact assessment (simple public offering type proposal) ▽ Environmental impact survey (general competitive bidding
In January, it published the environmental impact assessment (environmental assessment) manual, which had been entrusted to the Construction Technology Research Institute. The total project cost was about 30 billion yen, and the project period was expected to be about 10 years in the evaluation at the time of adoption of the new project (FY 2018). In the restoration project, the gravity dam section and the left and right bank fill dam section will be raised by 2 meters each. At the same time, the existing spillway section was improved and the spillway section was expanded. When the project is completed, the embankment height will be 52 meters, and the crest length of 480 meters will be extended to 560 meters.
In March of last year, the office established the "Technical Review Committee for Environmental Impact Assessment of the Kitakami River Upstream Dam" to implement the project. Formulate a method manual with advice from academics who specialize in the environmental field. Work such as the "reconstruction of the Yosishida Dam body design" and planning studies was outsourced to Nippon Koei.
