Editing Rapid City, South Dakota (section)

===1972 Rapid Creek flood===
{{Main|1972 Black Hills flood}}
[[Image:Rapid City SD wea00703.jpg|thumb|Cars thrown together by the 1972 flood]]
On June 9–10, 1972, extremely heavy rains over the eastern [[Black Hills]] of South Dakota produced record floods on Rapid Creek and other streams in the area. Nearly {{convert|15|in|mm}} of rain fell in about six hours near [[Nemo, South Dakota|Nemo]], and more than {{convert|10|in|mm}} of rain fell over an area of {{convert|60|sqmi|km2|-1}}. According to the [[Red Cross]], the resulting peak floods (which occurred after dark) left 238 people dead and 3,057 people injured.<ref>{{cite web | title = The 1972 Black Hills-Rapid City Flood Revisited | publisher = United States Geological Survey | access-date=October 15, 2007 | url = http://sd.water.usgs.gov/projects/1972flood/ | archive-url = https://web.archive.org/web/20071009114711/http://sd.water.usgs.gov/projects/1972flood/ | archive-date=October 9, 2007 | url-status = dead }}</ref> Total property destruction was estimated in excess of $160 million (about $964 million in 2018 dollars), which included 1,335 homes and 5,000 automobiles that were destroyed. The flood also nearly destroyed a popular children's park: [[Story Book Island]].<ref>{{cite web | url=https://www.keloland.com/news/local-news/storybook-island-in-rapid-city-reflects-on-the-1972-flood/ | title=Storybook Island in Rapid City reflects on the 1972 flood | date=June 6, 2022 }}</ref> The flood also destroyed a predominantely Native American neighborhood and disproportionately killed and displaced the city's Native population.<ref>Erasing Indian Country: Urban Native Space and the 1972 Rapid City Flood. Stephen R. Hausmann. Western Historical Quarterly. Autumn, 2021. Accessed: May 1, 2025. https://academic.oup.com/whq/article-abstract/52/3/305/6297544</ref>

Runoff from this storm produced record floods (highest peak flows recorded) along Battle, Spring, Rapid, and Box Elder creeks. Smaller floods also occurred along Elk and [[Bear Butte]] creeks. Canyon Lake Dam, on the west side of Rapid City, broke the night of the flood, unleashing a wall of water down the creek. The 1972 flooding has an estimated recurrence interval of 500 years,<ref>[https://pubs.er.usgs.gov/pubs/ofr/ofr96202 (Burr and Korkow, 1996)]{{Dead link|date=April 2025 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> which means that a flood of this magnitude will occur on average once every 500 years. Every year there is a 0.2% chance (1 in 500) that a similar event will occur. To prevent similar damage, the city has prohibited residential and business construction on its flood plain. Today the flood plain is used for civic functions such as golf courses, parks, sports arenas, and arboretums, based mostly on the landscape and temporary use by people.

In 2007, the [[Rapid City Public Library]] created a 1972 Flood digital archive<ref>[http://www.rapidcitylibrary.org/lib_info/1972Flood/index.asp 1972 Flood digital archive] {{webarchive|url=https://web.archive.org/web/20120210213624/http://www.rapidcitylibrary.org/lib_info/1972Flood/index.asp |date=February 10, 2012}}</ref> that collects survivors' stories, photos and news accounts of the flood. The Journey Museum has an interactive display on the 1972 flood; this is an ongoing project to give future generations the best idea of how the people were affected and what changes the city made as a result of the major losses of life and property. Plans include the memorialization of all those who died from the flood by the preparation of individual biographies, so they may be remembered more fully.