is an

artificial lake A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including contro ...

located in Midori-ku,

Sagamihara is a city in Kanagawa Prefecture, Japan. , the city has an estimated population of 723,470, with 334,812 households, and a population density of 1,220 persons per km2. The total area of the city is . Sagamihara is the third-most-populous city ...

Kanagawa is a Prefectures of Japan, prefecture of Japan located in the Kantō region of Honshu. Kanagawa Prefecture is the List of Japanese prefectures by population, second-most populous prefecture of Japan at 9,221,129 (1 April 2022) and third-dens ...

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

Kantō region The is a geographical area of Honshu, the largest island of Japan. In a common definition, the region includes the Greater Tokyo Area and encompasses seven prefectures: Gunma, Tochigi, Ibaraki, Saitama, Tokyo, Chiba and Kanagawa. Slight ...

. Created in 1947 after the

Sagami River The is a river in Kanagawa Prefecture, Kanagawa and Yamanashi Prefecture, 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 ...

was

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, a ...

med, it serves as use for

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 pleasur ...

al and

hydroelectric Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and ...

purposes. The lake also served as venue for

canoeing Canoeing is an activity which involves paddling a canoe with a single-bladed paddle. Common meanings of the term are limited to when the canoeing is the central purpose of the activity. Broader meanings include when it is combined with other acti ...

events at the

1964 Summer Olympics The , officially the and commonly known as Tokyo 1964 ( ja, 東京1964), were an international multi-sport event held from 10 to 24 October 1964 in Tokyo, Japan. Tokyo had been awarded the organization of the 1940 Summer Olympics, but this ho ...

held in

Tokyo Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, with an estimated 37.468 ...

, located from the lake.1964 Summer Olympics official report Volume 1, Part 1.
p. 131. Accessed September 11, 2008.

Water and land usage surrounding the lake

Typical lake flows (in m³/s) are 85 hydroelectric, 10.34 domestic, 4.16

irrigation Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow Crop, crops, Landscape plant, landscape plants, and Lawn, lawns. Irrigation has been a key aspect of agriculture for over 5,00 ...

, and 2.15 industrial. Land usage is 87.5% natural, 4.6%

agricultural Agriculture or farming is the practice of cultivating Plant, plants and livestock. Agriculture was the key development in the rise of Sedentism, sedentary human civilization, whereby farming of Domestication, domesticated species created food ...

, and 7.9% other.

Eutrophication Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytopla ...

issues have been a serious issue of the lake that was first observed in 1967. The main issue was microcystis

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

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 A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place", or a plant growing where it is not wanted.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. ...

s while most crops grown are

rice Rice is the seed of the grass species ''Oryza sativa'' (Asian rice) or less commonly ''Oryza glaberrima ''Oryza glaberrima'', commonly known as African rice, is one of the two domesticated rice species. It was first domesticated and grown i ...

and

vegetable Vegetables are parts of plants that are consumed by humans or other animals as food. The original meaning is still commonly used and is applied to plants collectively to refer to all edible plant matter, including the flowers, fruits, stems, ...

Fertilizer A fertilizer (American English) or fertiliser (British English; see spelling differences) is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from ...

application for crops near the lake is moderate.

Recreational uses

Because of the lake's creation in 1947, it displaced the

career The career is an individual's metaphorical "journey" through learning, work and other aspects of life. There are a number of ways to define career and the term is used in a variety of ways. Definitions The ''Oxford English Dictionary'' defin ...

s of many local fishermen in the area.Green Gables information on Lake Sagami
. Accessed September 9, 2008. 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 Smelt may refer to: * Smelting, chemical process * The common name of various fish: ** Smelt (fish), a family of small fish, Osmeridae ** Australian smelt in the family Retropinnidae and species ''Retropinna semoni'' ** Big-scale sand smelt ''At ...

black bass Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white have of ...

from the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

was imported to the lake as was Prussian

carp Carp are various species of oily freshwater fish from the family Cyprinidae, a very large group of fish native to Europe and Asia. While carp is consumed in many parts of the world, they are generally considered an invasive species in parts of ...

. Because of the bass, the lake is a popular

recreational fishing Recreational fishing, also called sport fishing or game fishing, is fishing for leisure, exercise or competition. It can be contrasted with commercial fishing, which is professional fishing for profit; or subsistence fishing, which is fishing ...

area. The lake is also used for couples

dating Dating is a stage of romantic relationships in which two individuals engage in an activity together, most often with the intention of evaluating each other's suitability as a partner in a future intimate relationship. It falls into the categor ...

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.

Water treatment

In 1984, there were 170 industrial and four municipal

sewage treatment Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable for discharge to the surrounding envir ...

plants surrounding the lake.

References

External links

{{Authority control Venues of the 1964 Summer Olympics Olympic canoeing venues

Sagami Sagami may refer to: * Sagami, an 11th-century ''waka'' poet *Sagami Province, an old province in Japan *Sagami River, a river in Kanagawa and Yamanashi *Sagami Bay, a bay south of Kanagawa Prefecture in Honshū *Sagami Line, a railway roughly along ...

Sagamihara Landforms of Kanagawa Prefecture