Sagami River
Encyclopedia
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 . The river overall was sometimes referred to as the from the sweetfish (ayu) which were once abundant in its waters.
The Sagami River drains Lake Yamanaka
, the largest and easternmost of the Fuji Five Lakes
in Yamanashi Prefecture. It loops northwest, then northeast through Yamanashi, before following a generally southerly course to exit into Sagami Bay
of the Pacific Ocean
between the cities of Hiratsuka
and Chigasaki
. It is dammed at several locations along the way, forming a number of reservoir lakes, the largest of which are Lake Sagami
and Lake Tsukui.
The river has had to re-cut its course several times due to repeated eruptions of Mount Fuji
, and river terraces are in evidence along its upper reaches in Yamanashi. As the river crosses Kanagawa, it forms natural levees in the soft soils of the alluvial plain
s of central Kanagawa, and forms almost no river delta
as it exits into the ocean.
The potential of the upper reaches 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
-Kanagawa
industrial belt, and the growing need for a reliable supply of drinking and industrial water. Work on the Sagami Dam
began in 1938; however, lack of funding and the advent of World War II
delayed completion until after the end of the war. In the post war period, the Shiroyama Dam
was also completed on the main stream of the Sagami River in 1965. A number of dams have also been completed on the Nakatsu River, the main tributary
of the Sagami River, including the Miyagase Dam
.
35.315168°N 139.36925°W (mouth)
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...
in Kanagawa
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...
and Yamanashi
Yamanashi Prefecture
is a prefecture of Japan located in the Chūbu region of the island of Honshū. The capital is the city of Kōfu.-Pre-history to the 14th century:People have been living in the Yamanashi area for about 30,000 years...
Prefectures 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...
.
The upper reaches of the river in Yamanashi prefecture are also sometimes known as the , and the portion near the river mouth as the . The river overall was sometimes referred to as the from the sweetfish (ayu) which were once abundant in its waters.
The Sagami River drains Lake Yamanaka
Lake Yamanaka
is the biggest of the Fuji Five Lakes. Located in Yamanashi Prefecture near Mount Fuji, Japan, the lake is used for boating, fishing, water-skiing, windsurfing, sightseeing and swimming. If the wind comes from the west, the lake provides a smooth lift for paragliding at Mount Myouyama. There are...
, the largest and easternmost of the Fuji Five Lakes
Fuji Five Lakes
is the name of the area located at the base of Mount Fuji in the Yamanashi prefecture of Japan. It has a population of about 100,000. and sits approximately 1,000 meters above sea level. The name Fuji Five Lakes comes from the fact that there are five lakes formed by previous eruptions of Mount Fuji...
in Yamanashi Prefecture. It loops northwest, then northeast through Yamanashi, before following a generally southerly course to exit into Sagami Bay
Sagami Bay
Sagami Bay , also known as the Sagami Gulf or Sagami Sea, lies south of Kanagawa Prefecture in Honshū, central Japan, contained within the scope of the Miura Peninsula, in Kanagawa, to the east, the Izu Peninsula, in Shizuoka Prefecture, to the west, and the Shōnan coastline to the north, while the...
of the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
between the cities of Hiratsuka
Hiratsuka, Kanagawa
is a city located in Kanagawa Prefecture, Japan. As of 2010, the city had an estimated population of 259,991 and the density of 3,830 persons per km²...
and Chigasaki
Chigasaki, Kanagawa
is a city located in central, Kanagawa Prefecture, Japan. As of 2010, the city had an estimated population of 234,400 and a density of 6,540 persons per km²...
. It is dammed at several locations along the way, forming a number of reservoir lakes, the largest of which are Lake Sagami
Lake Sagami
is an artificial lake located in Midori-ku, Sagamihara, Kanagawa in Japan's Kantō region. Created in 1947 after the Sagami River was dammed, it serves as use for recreational and hydroelectric purposes...
and Lake Tsukui.
The river has had to re-cut its course several times due to repeated eruptions of Mount Fuji
Mount Fuji
is the highest mountain in Japan at . An active stratovolcano that last erupted in 1707–08, Mount Fuji lies about south-west of Tokyo, and can be seen from there on a clear day. Mount Fuji's exceptionally symmetrical cone is a well-known symbol of Japan and it is frequently depicted in art and...
, and river terraces are in evidence along its upper reaches in Yamanashi. As the river crosses Kanagawa, it forms natural levees in the soft soils of the alluvial plain
Alluvial plain
An alluvial plain is a relatively flat landform created by the deposition of sediment over a long period of time by one or more rivers coming from highland regions, from which alluvial soil forms...
s of central Kanagawa, and forms almost no river delta
River delta
A delta is a landform that is formed at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river...
as it exits into the ocean.
The potential of the upper reaches 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, and the growing need for a reliable supply of drinking and industrial water. 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,...
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. In the post war period, 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 also completed on the main stream of the Sagami River in 1965. A number of dams have also been completed on the Nakatsu River, the 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, including the Miyagase Dam
Miyagase Dam
The is a dam on the Nakatsu River, a main tributary of the Sagami River in Aikō District, Kanagawa Prefecture on the island of Honshū, Japan. It straddles the border between the village of Kiyokawa, town of Aikawa and the former town of Tsukui The is a dam on the Nakatsu River, a main tributary...
.
External links
35.315168°N 139.36925°W (mouth)