0579-Imaichi Dam/Imaichi Dam

Location: Higashimata, Sashikabe, Nikko-shi, Tochigi
Date of interview: 10/02/2010

I ended up staying up all night to come to Tochigi to participate in the Yunishigawa Dam construction site tour (2010/10/02). When I participated in the previous tour of the Yashio Dam and the Snakeo River Dam, I had no choice but to take the Shinkansen bullet train because I had to work on the day before and after the tour.

View of the monument and the top from the right bank

The Imaichi Dam is owned by the Tokyo Electric Power Company (TEPCO) and serves as a lower reservoir for pure pumped-storage power generation with the Kuriyama Dam (0578-Kuriyama Dam) serving as the upper reservoir. An underground power plant (Imaichi Power Station) was built 100 m underground between the Imaichi Dam and the Kuriyama Dam, and the Imaichi Dam was constructed using aggregate from the excavation of the power station.

View of the top edge from the right bank

The time is 6:00 a.m. early in the morning, but it is autumn and somewhat dark. There are still lights on the street lamps. The top end of the dam is open to private vehicles. If you pass through the tunnel seen over there, you will reach the upstream side of the dam lake, but I cut it off due to time constraints. It seems to be a dead end after that.

View of Crest Gate

Two roller gates are installed at the crest.
In addition, the Imaichi Dam is also equipped with surface water intake facilities, with the following specifications

Name: Surface intake gate / Middle intake gate
Type : 3-stage roller gate / roller gate
Net diameter x door height: 1.50m x 21.50m / 1.50m x 1.00m
Number of gates: 1 / 1
Opening/Closing speed: 0.3m/min / 0.3m/min
Door weight: 11.0t / 0.9t
Date of production: September 1986
Production: Ishikawajima-Harima Heavy Industries Co.

View of the outlet from Kuriyama Dam

This is the outlet from the Kuriyama Dam.

View of the crest gate door body

Model: roller gate
Net diameter x door height: 6.25m X 8.354m
Number of gates: 2
Opening/closing speed: 0.3m/min
Door weight: 49.8t/portal
Date of production: September 1986
Production: Ishikawajima-Harima Heavy Industries Co.

View downstream from the top

Downstream you turn right. You have a road on the left bank. Let's go there later.

View of the embankment on the lake side of the dam from the left bank

Perhaps because I was sleepwalking, I was not paying attention to this at all, but as you can see from the photo, the water level is almost full at this time. As you can see from the photo, the water level was almost full at that time. It seems that there was some construction work going on at the power plant, and it was necessary to empty the Kuriyama Dam in the upper pond. I was told this information via twitter, and I was so ashamed of myself for not paying attention to it at all...

View of the downstream bank from the left bank

It gives a slender impression when viewed in this way. It also has an air of dignity that makes it hard to believe that it is a dam exclusively for power generation.

View of footing from left bank

A footing that seems to be impossible to get down. Unfortunately, it is not open. It is rather a relief that it is not open!

View of the top edge from the left bank

It is getting a little brighter. The lights from the street lamps are going out before we know it. However, there is a tunnel behind us, and even though it is getting much brighter, I was a little scared because of the sound of water that seems to be leaking in the tunnel and strange squeaking noises.

View of the dam lake from the top

After passing through that tunnel, you will come to a bridge that can be seen over there. From that bridge, you can see the dam lake and the embankment. Since I was driving, I should have driven faster.

View of the embankment on the lake side from the right bank

It is quiet. No one is here and no one is coming. The only sound is the sound of the water. This atmosphere is not bad. Well then! Let's go downstream!

Off-limits areas on the downstream side of the road

But then we came to a dead end because of a fence. We had crossed a large puddle on the way there, and yet here we were. We were so disappointed.
Incidentally, the road to the skyline has a series of curves, but it seems to be an ideal training ground for drifters. I was relieved that I did not come here in the middle of their practice when I saw a large number of slip tracks on the road surface and a large number of anti-collision tires piled up on the slope. (I'd love to see them, but be warned, it's illegal.)

dam characteristics

Other facilities/observations

The PR exhibition hall is located on the Kinugawa River, a short distance from the Imaichi Dam.TEPCO Kinugawa LandThe "TEPCO Kinugawa Land" is available. For a more detailed tour of the power plant and other facilities, you can apply for a free tour at TEPCO Kinugawa Land. However, it seems to be limited to groups.
Hours: 9:00-16:30
Closed: Wednesdays (or the following day if Wednesday is a national holiday)
Closed.

Accommodations that may be close to Imaichi Dam