The following announcement was made on Twitter by the Tenryu River Dam Integrated Management Office. The water in the reduction works of the Kosibu Dam will be drained and the dam will be opened to the public!
The timing was just right that the number of people infected with the new coronavirus had decreased considerably and we could move freely, although we had to take countermeasures. Thinking that such an opportunity would rarely present itself, I went there on November 27, when it would be open at night and illuminated.
Looking downstream from the right bank
We arrived at the Kosibu Dam a little after 9:00. This season tends to be backlit.
Reception in front of the elevator tower
Complete the reception desk. We then signed our names, sprayed alcohol on our hands, borrowed helmets, and boarded the elevator. We are not allowed to talk in the elevator.
View of the abatement pond from the catwalk
Instead of going into the abatement works, I decided to first walk the catwalk at the bottom and take a look inside the abatement pond. I put aside Mr. Muska's line, "People look like trash! I am very nervous because this is my first experience to see the empty abatement pond.
Stairs to the abatement pond
Finally, we descended the last set of steps leading to the abatement pond. The treads were so thin that I almost stepped off if I was not careful.
footing staircase
I have been doing heavy work since the summer, so I must have gained a lot of strength, but even so, the stairs made me short of breath.
Looking up the embankment from the abatement pond
It's not often in life that you get to look up at the dike from closer to the foundation rock, but I couldn't be bothered with all that when I have a cervical hernia.
within a force majeure pond
This is a view looking downstream from about the center of the embankment side of the force-reducing basin. Although the reduction pool is often compared to a swimming pool, it is so huge that it looks more like a dock at a shipyard that handles tankers and other large vessels than a swimming pool.
Sediment in abatement ponds
This photo reminds us that sediment accumulates unexpectedly in the abatement pond. Some of the stones are quite large, which is surprising.
Floor of abatement works "water slap"
And the floor of the abatement works (water tap) is so rugged. It is a precious sight, as I had no idea that it would be in such a state if the water had not been drained.
sil (unit of volume, approx. 1.8 ml)
A trapezoidal structure called a sill is installed in the center of the abatement pond. This is another structure that would not have been visible without the water. I assume that the sills are used to reduce the flow of water into the abatement pond by causing it to jump, but I wish I had checked the sills properly. Steel is attached to the corners of the sill to prevent it from being scraped off.
sub-dam
We came to the sub-dam, which is indeed huge when seen up close.
drainage hole
This drainage hole is located at the bottom of the sub-dam. It seems that the water from the reduction basin was pumped up and let out through this hole.
Looking through the drainage hole...
I thought I could see beyond the sub-dam, but unfortunately I couldn't💦.
Downstream view of the embankment from the sub-dam in the reduction basin
I attended the morning session, but it would have been better to attend the afternoon session because the levee was in shadow.
View of the sub-dam from the right bank
We moved from inside the abatement pond to the right bank. Normally the pond is filled with water, but when viewed from above without water, the size of the pond is more apparent.
Incidentally, I had photographed the sub-dam in almost the same position during the Kosibu Dam Open Day event seven years ago, so I have included it for your reference.
Looking downstream from the sub-dam on the right bank
The downstream face of the embankment. The area below the conduit gate looks black and dirty. Am I the only one who would like to wash it with a high-pressure washer? (Please hold such an event!).
View of the load-reducing structure from the top of the tower over the elevator tower
We returned to the top edge. It is a strange and precious sight to see from the top end that there is no water stored in the abatement pond where water is usually stored.
View of the downstream face of the embankment and reduction works from the left bank
It is a precious sight, so I took pictures from the left bank as well.
Kosibu Dam Curry
It was lunchtime, so we moved to the roadside station "Kabuki no Sato Oshika" and had Kosibu Dam Curry at Restaurant Oina, limited to 15 servings a day. It was well cooked and delicious. If you show your Kosibu Dam Card, you can get a coffee or dessert. On this day, we had soft ice cream.
View of the levee from the right bank observation platform
From the roadside station, I visited Miwa Dam, Takato Dam, and Katagiri Dam, and returned to Kosibu Dam in the evening. By the way, I thought I had visited Katagiri Dam in the past, but I realized after returning home that it was my first visit to the dam (lol).
Illuminated levee
Finally, the abatement open event begins the evening portion of the event. The lights are shining moderately on the embankment, which is also nice. I am happy to experience a tremendous sense of unreality.
Downstream view of the levee illuminated from around the sub-dam
I was very impressed by the smiles on the faces of the dam enthusiasts who were touring the site from start to finish. The pictures don't do it justice, but seeing it in person is definitely breathtaking and extremely moving.
Levee reflecting in a pool of water in the abatement pond
It is not often that one can see such a scene. Words cannot express how wonderful it is.
Looking downstream from the left bank corner of the reduction basin
A follower told me that "the atmosphere at the corner (of the abatement pond) is the best," so I moved on, wading through the water that was up to my ankles in a zabazaba. Then, there was the breathtaking sight of the Kosibu Dam towering above us. The sub-dam, especially on the left bank, is in the shadow, but the water is pooled like a water mirror, creating a fantastic view like this.
skyline at night
After enjoying the abatement pond, I returned to the top of the dam. This was the first time to see the Kosibu Dam at night, so I took some pictures of the top edge.
View of the levee from the right bank observation platform
And the Kosibu Dam at night from the right bank observation deck, which I had not seen yet. It has a great atmosphere. And there is no water in the reduction works. After seeing this for the last time, I headed home.
And this event will be awarded the Japan Dam Award 2021 event prize. And for the third time in two consecutive years! Congratulations again 🎊
The content of the event was such that it seemed as if they were trying to win the Dam Award, but the flexibility of the Tenryu River Dam Integrated Management Station staff in their ideas and their drive to entertain was reflected in the smiles of the visitors, which I think said it all.
Thank you so much.
Instadam Live
A bit of advertising, or rather, an announcement. Recently, when I visit dams, I have been broadcasting a live insta-stream. I also live-streamed the Kosibu Dam abatement opening event, and I have archived it for your viewing pleasure. Also, please follow me on Twitter 😉.
Comment