Shinaki Dam

I saw some kind of animal from the dam

Cool place to visit for dam fans

It is a volcanic acidic dam lake.

A super important dam that maintains the water quality of the metropolitan area. As you can see from Kusatsu Onsen at the foot of Mt. Shirane, which rises in the northwestern part of Gunma Prefecture, it contains a lot of sulfur, and the rain and snow that falls on Mt. Shirane flows into the river with a strong acidity of ph2-4. Acidic water corrodes iron and concrete such as the Shirasuna River (the name suggests that sulfur components are attached to the riverbank) and the Agatsuma River, and aquatic organisms can live there. It will become a "death river" and will adversely affect the quality of the water supply in the eastern part of Tokyo, which draws water from the Edo River downstream of the Tone River system. Therefore, in 1957, we started the world's first neutralization project for acidic rivers by building a dam here and adding alkaline lime. In addition, the river that flows out of Mt. Kusatsu-Shirane contains high levels of arsenic, which are also suppressed below the standard value by precipitating at this dam, which is exactly the secret weapon for maintaining the water quality of the Tone River system. In addition, there is a facility called "Environmental Experience Amusement" in Kusatsu Onsen, which is located upstream, and in addition to distributing dam cards, it is said that you can observe the neutralization factory and the input of lime. It's called a tour of the construction site of the Yamba dam, and it's called here. Recently, the Ministry of Land, Infrastructure, Transport and Tourism is open to information disclosure, and it's a nice death.

A dam to neutralize the acidity of Kusatsu. It works similar to a slag dam that sediments and separates toxic components downstream of the mine. The color of the water in Oku Shimanko (Shimandam Lake) next to the east is called 40,000 blue, but this Joshu Yuko is an emerald green that is so wonderful that you can call it Shinagi Green or Kusatsu Green. Is. It is also characteristic that it smells sour on hot days. The colors of red, yellow, and orange are added during the fall foliage season, so you won't get tired of looking anywhere around the lake.