森と湖に親しむ旬間2009～丸山ダム～

."Season for Familiarization with Forests and LakesThe 2009 event was held at Yokoyama Dam and this Maruyama Dam.
At Maruyama Dam, the event included not only a tour of the inside of the embankment, but also a quick ascent from the elevator on the first floor to the "Gate Pier" at the top of the embankment, from where visitors could enjoy a panoramic view.

Unfortunately, the weather was unfavorable on this day, but the rain the day before made it a miraculous event, as we were even able to see the powerful discharge of the fish.

At the bottom of the page you will also find a video of the discharge as seen from the gate pier and the bridge downstream.

>>Please also see the article on Maruyama Dam.
>>Maruyama Dam (Gifu)

data display panel

First of all, we were shown around the control center. The dam is an old dam, so the equipment looks quite old.
This is a data display panel that allows the current status of the Maruyama Dam to be viewed as numbers from various angles.

Gate control console

This is the so-called "dam control. The authority to operate the gates is also on the KEPCO side, but when the inflow volume is such that flood control is required, the authority is delegated to the Ministry of Land, Infrastructure, Transport and Tourism.

Kiso River system rainfall water level display panel

This display panel shows the rainfall and water level of the Kiso River system. If you think about it, the main stream of the Kiso River system upstream from the Maruyama Dam is only a dam for power generation until the Misogawa Dam in the Kiso River Basin in Nagano Prefecture. In other words, the Maruyama Dam is almost single-handedly supporting the inflow of water between the two dams, and just thinking about it made me realize how much I appreciate the Maruyama Dam. (The only other dam for flood control is the Nakanokata Dam on a tributary of the Kiso River.)

information processing console

It is the "brain of the dam," so to speak, that calculates the optimal gate operation based on various data such as rainfall, inflow, water level, etc.

View near the sub-dam from the side of the control center

I went out from the control center to enter the dike. Still, it was a great discharge. The roar of the discharge sounded like an earth tremor. I had never seen such a discharge before.

View of the discharge from just below the levee

Here, how do you like it! No, it's already a storm of excitement.

Auditor's corridor entrance

We moved to the area just below the levee, with the sight of the fish being discharged in the water behind us. This area is normally off-limits to visitors. It is off-limits to visitors only for events such as this.

Looking up at the embankment from directly below

The soaring embankment! It is truly a masterpiece. It is wet with rain and looks jet black, but it also has a wonderful expression like an old soldier who has fought many battles in the past.

Character for "motion in stillness" by Shiro Ohtagaki

The words "Motion in Stillness" are written above the entrance to the inside of the dike. The words were written by Mr. Shiro Otagaki, the president of KEPCO at that time. Mr. Otagaki is a person who should not be forgotten in the history of power generation dams, as he was instrumental in the construction of the Kurobe Dam (0848 - Kurobe Dam).

The phrase "Do-Chuchu-Jo" means to keep one's cool and look ahead to the future, even in the midst of turmoil.

It can also be taken to mean that even in quiet times, one should be able to judge the surrounding situation and take action at any time, but from the perspective of the historical background and dam management, we have judged it to be "quiet in motion. This is not a reading from literature, etc., but rather Kamima's one-sided subjective view. It is unclear which meaning President Ohtagaki meant by the phrase, or whether he meant both, but either way, it is a phrase that we appreciate.

Concrete surface

The surface of the concrete is not as fine as it is today, but the ruggedness of the surface is reminiscent of a soldier who has fought many battles in the past. This is the concrete that tells the whole story of the Maruyama Dam.

inside the audit corridor

Now we come to the interior of the audit corridor. It appears to be quite dilapidated and has many leaks.

They say it's leaking heavily.

Voila. Even though it still functions as a dam or has no problem in this condition, if this condition continues...it is not so good, is it? Since then, the government has shifted from the LDP to the DPJ, and it seems that Minister of Land, Infrastructure, Transport and Tourism Maehara has stopped the construction of the new Maruyama Dam, but the old soldier wants to retire already, don't you think?

Discharge of water from the gate pier

We took the elevator all the way to the top end. From there, we went up the stairs to the top of the gate pier. The Maruyama Dam is now mine. I was moved to tears at the thought of seeing such a discharge from above.

Wire hoisting machine

It is indeed thick! I would like to see it move.

View downstream from Gate Pier

The water that flowed out of the gate went downstream at once, scattering a roaring sound.

View of the dam lake from the top

On the other hand, the dam lake side is quiet. There is even some gas and a phantom-like atmosphere. And the old soldiers are taking it all in their hands...that's the impression I got.

Line of the planned construction of the new Maruyama Dam

Now, we moved to the left bank to the site of the aggregate plant. On the way, he guided us to the place where the line for the planned construction of the new Maruyama Dam has been set up. The red and white line in front is the lake side of the embankment, and the other side is the downstream side of the embankment. This is where the new Maruyama Dam will be constructed.

Aggregate plant site

It is a strange sight to see again and again.

Incidentally, just before this, we encountered a wild boar. I only saw its rear view momentarily, so I could not photograph it....

View of the levee from the bridge downstream

And finally, we have moved to the bridge downstream. This time we are looking directly at the discharge. I am very sorry that the photo is a bit skewed.

The tour ended here. Ah, it was a great day.