Lake Sagami
Encyclopedia
is an artificial lake
located in Midori-ku
, Sagamihara, Kanagawa
in Japan
's Kantō region
. Created in 1947 after the Sagami River
was dam
med, it serves as use for recreation
al and hydroelectric purposes. The lake also served as venue for canoeing
events at the 1964 Summer Olympics
held in Tokyo
, located 60 kilometres (37.3 mi) from the lake.
, and 2.15 industrial. Land usage is 87.5% natural, 4.6% agricultrual
, and 7.9% other. Eutrophication
issues have been a serious issue of the lake that was first observed in 1967. The main issue was microcystis algae
bloom and reached its highest cell count of 2,500,000 cells/mL in July-October 1979 (data from 1985). Most vegetation grown around the lake are grassland and weed
s while most crops grown are rice
and vegetable
s. Fertilizer
application for crops near the lake is moderate.
s of many local fishermen
in the area. In return for their livelihood being taken away, many of these families were offered rental boats in the new lake. No private boats are allowed on the lake as a result. To compensate for the loss of the smelt, black bass
from the United States
was imported to the lake as was Prussian carp
. Because of the bass, the lake is a popular recreational fishing
area. The lake is also used for couples dating
for boat rides and families. Row boat standard daily rental rates are ¥
3000 for one person, ¥4500 for two people, and ¥6000 for three people with hourly rates being more expensive.
plants surrounding the lake.
Reservoir
A reservoir , artificial lake or dam is used to store water.Reservoirs may be created in river valleys by the construction of a dam or may be built by excavation in the ground or by conventional construction techniques such as brickwork or cast concrete.The term reservoir may also be used to...
located in Midori-ku
Midori-ku, Sagamihara
is one of three wards of Sagamihara, Kanagawa, Japan, located in the west part of the city and covered about 77% area. The east of Midori-ku faces Chūō-ku; the north faces Machida and Hachiōji....
, Sagamihara, 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...
in 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...
's 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....
. Created in 1947 after 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...
was 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...
med, it serves as use for recreation
Recreation
Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or pleasure and are considered to be "fun"...
al and hydroelectric purposes. The lake also served as venue for canoeing
Canoeing at the 1964 Summer Olympics
Canoeing at the 1964 Summer Olympics was held between 20 October 1964 and 22 October 1964 on Lake Sagami, from Sagamiko, Kanagawa, Japan. There were 7 events, 5 of which were for men and 2 for women. Both of the women's events were 500 metre kayaking events; there were three kayaking and two...
events at the 1964 Summer Olympics
1964 Summer Olympics
The 1964 Summer Olympics, officially known as the Games of the XVIII Olympiad, was an international multi-sport event held in Tokyo, Japan in 1964. Tokyo had been awarded with the organization of the 1940 Summer Olympics, but this honor was subsequently passed to Helsinki because of Japan's...
held in Tokyo
Tokyo
, ; officially , is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of Japan. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family...
, located 60 kilometres (37.3 mi) from the lake.
Water and land usage surrounding the lake
Typical lake flows (in m3/s) are 85 hydroelectric, 10.34 domestic, 4.16 irrigationIrrigation
Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...
, and 2.15 industrial. Land usage is 87.5% natural, 4.6% agricultrual
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
, and 7.9% other. Eutrophication
Eutrophication
Eutrophication or more precisely hypertrophication, is the movement of a body of water′s trophic status in the direction of increasing plant biomass, by the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers or sewage, to an aquatic system...
issues have been a serious issue of the lake that was first observed in 1967. The main issue was microcystis algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
bloom and reached its highest cell count of 2,500,000 cells/mL in July-October 1979 (data from 1985). Most vegetation grown around the lake are grassland and weed
Weed
A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...
s while most crops grown are rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...
and vegetable
Vegetable
The noun vegetable usually means an edible plant or part of a plant other than a sweet fruit or seed. This typically means the leaf, stem, or root of a plant....
s. Fertilizer
Fertilizer
Fertilizer is any organic or inorganic material of natural or synthetic origin that is added to a soil to supply one or more plant nutrients essential to the growth of plants. A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use...
application for crops near the lake is moderate.
Recreational uses
Because of the lake's creation in 1947, it displaced the careerCareer
Career is defined by the Oxford English Dictionary as a person's "course or progress through life ". It is usually considered to pertain to remunerative work ....
s of many local fishermen
Artisan fishing
Artisan fishing is a term used to describe small scale low-technology commercial or subsistence fishing practices. The term particularly applies to coastal or island ethnic groups using traditional techniques such as rod and tackle, arrows and harpoons, throw nets and drag nets, and traditional...
in the area. In return for their livelihood being taken away, many of these families were offered rental boats in the new lake. No private boats are allowed on the lake as a result. To compensate for the loss of the smelt, black bass
Black bass
Micropterus , is a genus of freshwater fish in the sunfish family of order Perciformes. The type species is M. dolomieu, the smallmouth bass...
from the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
was imported to the lake as was Prussian carp
Carp
Carp are various species of oily freshwater fish of the family Cyprinidae, a very large group of fish native to Europe and Asia. The cypriniformes are traditionally grouped with the Characiformes, Siluriformes and Gymnotiformes to create the superorder Ostariophysi, since these groups have certain...
. Because of the bass, the lake is a popular recreational fishing
Recreational fishing
Recreational fishing, also called sport fishing, is fishing for pleasure or competition. It can be contrasted with commercial fishing, which is fishing for profit, or subsistence fishing, which is fishing for survival....
area. The lake is also used for couples dating
Dating (activity)
Dating is a form of courtship consisting of social activities done by two persons with the aim of each assessing the other's suitability as a partner in an intimate relationship or as a spouse...
for boat rides and families. Row boat standard daily rental rates are ¥
Japanese yen
The is the official currency of Japan. It is the third most traded currency in the foreign exchange market after the United States dollar and the euro. It is also widely used as a reserve currency after the U.S. dollar, the euro and the pound sterling...
3000 for one person, ¥4500 for two people, and ¥6000 for three people with hourly rates being more expensive.
Water treatment
In 1984, there were 170 industrial and four municipal sewage treatmentSewage treatment
Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants from wastewater and household sewage, both runoff and domestic. It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants...
plants surrounding the lake.