Iwanuma (岩沼市, Iwanuma-shi) is a city located in Miyagi Prefecture, Japan. As of 31 March 2020[update], the city had an estimated population of 43,946 in 18,062 households,[1] and a population density of 730 persons per km². The total area of the city is 60.45 square kilometres (23.34 sq mi). Iwanuma is at the convergence of two ancient roads, the Tōkaidō and the Rikuzen-Hama Kaidō.
Geography
Iwanuma is in the east-center Miyagi Prefecture, bordered by the Pacific Ocean to the east. It is also located at the mouth of the Abukuma River.
Iwanuma has a humid climate (Köppen climate classificationCfa) characterized by mild summers and cold winters. The average annual temperature in Iwanuma is 12.6 °C. The average annual rainfall is 1252 mm with September as the wettest month. The temperatures are highest on average in August, at around 24.9 °C, and lowest in January, at around 1.6 °C.[2]
Demographics
Per Japanese census data,[3] the population of Iwanuma has recently plateued after a long period of growth.
Historical population
Year
Pop.
±%
1920
15,428
—
1930
17,524
+13.6%
1940
18,490
+5.5%
1950
25,303
+36.8%
1960
26,452
+4.5%
1970
29,822
+12.7%
1980
34,910
+17.1%
1990
38,091
+9.1%
2000
41,407
+8.7%
2010
44,187
+6.7%
2020
44,068
−0.3%
History
The area of present-day Iwanuma was part of ancient Mutsu Province, and the Takekoma Inari Shrine claims to have been founded in 842 AD. Mention of “Iwanuma Castle” appears in early Muromachi period documents. The area came under the control of the Date clan of Sendai Domain during the Edo period, under the Tokugawa shogunate. The town of Iwanuma was established on June 1, 1889 with the establishment of the modern municipalities system.
The village of Okuma merged with Iwanuma on January 11, 1947, followed by Sengan and Tamaura on April 1, 1955. Iwanuma was raised to city status on November 1, 1971.
Iwanuma has a mayor-council form of government with a directly elected mayor and a unicameral city legislature of 20 members. Iwanuma contributes one seat to the Miyagi Prefectural legislature. In terms of national politics, the city is part of Miyagi 3rd district of the lower house of the Diet of Japan.
Education
Iwanuma has four public elementary school and four public middle schools operated by the city government, and one public high school operated by the Miyagi Prefectural Board of Education. The prefectural also operates a special education school for the handicapped.