Miyagase Dam
Encyclopedia
The is a dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...

 on the Nakatsu River, a main tributary
Tributary
A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Sagami River
Sagami River
The is a river in Kanagawa and Yamanashi Prefectures on the island of Honshū, Japan.The upper reaches of the river in Yamanashi prefecture are also sometimes known as the , and the portion near the river mouth as the...

 in Aikō District
Aiko District, Kanagawa
is an administrative district of Japan located in central Kanagawa Prefecture. It currently consists of only one town, Aikawa, and one village, Kiyokawa.-History:...

, Kanagawa Prefecture
Kanagawa Prefecture
is a prefecture located in the southern Kantō region of Japan. The capital is Yokohama. Kanagawa is part of the Greater Tokyo Area.-History:The prefecture has some archaeological sites going back to the Jōmon period...

 on the island of Honshū
Honshu
is the largest island of Japan. The nation's main island, it is south of Hokkaido across the Tsugaru Strait, north of Shikoku across the Inland Sea, and northeast of Kyushu across the Kanmon Strait...

, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. It straddles the border between the village of Kiyokawa
Kiyokawa, Kanagawa
is a village located in Aikō District, Kanagawa, Japan. As of 2010, the village had an estimated population of 3,556and a density of 49.9 persons per km². The total area is 71.29 km².-Geography:...

, town of Aikawa
Aikawa, Kanagawa
is a town located in Aikō District, Kanagawa Prefecture, Japan. As of February 1, 2010, the town had an estimated population of 41,513 and a density of 1,210 persons per km². The total area was 34.29 km².-Geography:...

 and the former town of Tsukui
Tsukui, Kanagawa
was a town located in Tsukui District, Kanagawa, Japan.On March 20, 2006 Tsukui, along with the town of Sagamiko, also from Tsukui District, was merged into the expanded city of Sagamihara, and thus no longer exists as an independent municipality...

 (now part of the city of Sagamihara
Sagamihara, Kanagawa
is a city located in north central Kanagawa Prefecture, bordering Tokyo, Japan. It is the third most populous city in the prefecture, after Yokohama and Kawasaki, and the fifth most populous suburb of Greater Tokyo. Its northern neighbor is Machida, with which a cross-prefectural merger has been...

.

History

The potential of the Sagami River for hydroelectric power development began to be developed in the 1930s, with the growth of industry and electrical consumption in the Yokohama
Yokohama
is the capital city of Kanagawa Prefecture and the second largest city in Japan by population after Tokyo and most populous municipality of Japan. It lies on Tokyo Bay, south of Tokyo, in the Kantō region of the main island of Honshu...

-Kanagawa
Kawasaki, Kanagawa
is a city located in Kanagawa Prefecture, Japan, between Tokyo and Yokohama. It is the 9th most populated city in Japan and one of the main cities forming the Greater Tokyo Area and Keihin Industrial Area....

 industrial belt. Work on the Sagami Dam
Sagami Dam
The is a multi-purpose dam on the main stream Sagami River in Sagamihara, Kanagawa Prefecture on the island of Honshū, Japan.-History:The potential of the Sagami River valley for hydroelectric power development began to be developed in the 1930s, with the growth of population in the Shonan region,...

, the first dam on the main stream of the Sagami River began in 1938; however, lack of funding and the advent of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 delayed completion until after the end of the war. Work on the Shiroyama Dam
Shiroyama Dam
The is a multi-purpose dam on the main stream Sagami River in Sagamihara, Kanagawa Prefecture on the island of Honshū, Japan.-History:The potential of the Sagami River valley for hydroelectric power development began to be developed in the 1930s, with the growth of industry and electrical...

 was completed in 1965. The growth in population of nearby Atsugi
Atsugi, Kanagawa
is a city located in central Kanagawa Prefecture, Japan. As of 2010, the city has an estimated population of 225,622 and a population density of 2,410 persons per km². The total area was 93.83 km²...

 and increased need for industrial and drinking water spurred plans for additional dams on the Sagami River’s tributaries. Plans for the Miyagase Dam were finalized in 1969 with work commencing in 1971. Due to the huge size of the dam, and the need relocate some 300 households from the area flooded by the dam, construction was not completed until the year 2000.

Design

The Miyagase Dam is a hollow-core concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

 gravity dam. It was designed and built by a consortium of the Kajima Construction
Kajima Construction
( is a Japanese construction company. Founded in 1840, the company has its headquarters in Moto-Akasaka, Minato, Tokyo. The company is known for its DIB-200 proposal.-Demolition Technology:...

, Obayashi Corp.
Obayashi Corp.
is one of five major Japanese construction companies along with Shimizu Corporation, Takenaka Corporation, Kajima Corporation, and Taisei Corporation. It is one of the Nikkei 225 corporations. Headquarters are in Minato, Tokyo....

 and the Toda Corporation. The dam was designed as a multi-purpose dam. In addition to providing flood control
Flood control
In communications, flood control is a feature of many communication protocols designed to prevent overwhelming of a destination receiver. Such controls can be implemented either in software or in hardware, and will often request that the message be resent after the receiver has finished...

, it provides 90% of the tap water
Tap water
Tap water is a principal component of "indoor plumbing", which became available in urban areas of the developed world during the last quarter of the 19th century, and common during the mid-20th century...

 to two-thirds of the population of Kanagawa Prefecture, including the cities of Kawasaki
Kawasaki, Kanagawa
is a city located in Kanagawa Prefecture, Japan, between Tokyo and Yokohama. It is the 9th most populated city in Japan and one of the main cities forming the Greater Tokyo Area and Keihin Industrial Area....

, Yokohama
Yokohama
is the capital city of Kanagawa Prefecture and the second largest city in Japan by population after Tokyo and most populous municipality of Japan. It lies on Tokyo Bay, south of Tokyo, in the Kantō region of the main island of Honshu...

 and Yokosuka
Yokosuka, Kanagawa
is a city located in Kanagawa, Japan. As of 2010, the city had an estimated population of 419,067 and a population density of 4,160 people per km². It covered an area of 100.62 km²...

. It also provides water to the associated Aikawa Hydroelectric Power Plant, which has a rated capacity of 24,000 KW of power.

The 156 metres (511.8 ft) tall dam is the second tallest in the Kantō region
Kanto region
The is a geographical area of Honshu, the largest island of Japan. The region includes the Greater Tokyo Area and encompasses seven prefectures: Gunma, Tochigi, Ibaraki, Saitama, Tokyo, Chiba, and Kanagawa. Within its boundaries, slightly more than 40 percent of the land area is the Kantō Plain....

.

The reservoir created by the dam, is a popular recreation spot in Kanagawa Prefecture.

Surroundings

Public access to the dam and its lake are by Japan National Rote 412
Route 412 (Japan)
National Route 412 is a national highway of Japan connecting Hiratsuka, Kanagawa and Sagamihara, Kanagawa in Japan, with a total length of 48.6 km ....

.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK