Adapted from the book “Surviving the ’72 Flood,” with text by Seth Tupper and photographs by Johnny Sundby
There are places on the high limestone plateau of the western Black Hills where cool, clear springs bubble up from the ground.
Forks of spring-fed water merge into creeks, and the creeks flow eastward through pine forests, green meadows and eroded rock channels. They pick up additional water from rain, snow and tributaries along the way, and they fall thousands of feet in elevation before spilling out of the mountains.
Just west of Rapid City, one of those creeks rushes through a canyon, creating some of the town’s namesake rapids. After crossing the flats separating the Black Hills from an encircling hogback ridge, the creek cuts a gap in that ridge and flows through Rapid City, on its way to the western South Dakota plains.
Lakota speakers call this body of water “Mniluzahan,” meaning “Fast Water.” English speakers call it Rapid Creek.
The creek brings Rapid City a supply of treatable water, idyllic scenery, and habitat for fish and wildlife. It also brings floods.
Rapid City pioneers documented an 1878 flood that killed one person. A 1907 flood destroyed the first Canyon Lake dam on the creek just west of the city, but the dam was rebuilt in the 1930s. Numerous other periods of high water came and went. A degree of flood control was achieved in the 1950s with the construction of the massive Pactola dam and reservoir, high upstream in the Black Hills.
As Rapid City grew over the decades to a population of more than 40,000 by the 1970s, people built along the creek’s banks. Well-to-do residents pushed the city west as they erected comfortable waterfront homes. In the heart of the city, modest houses, trailer parks and businesses popped up in the floodplain.
The people who lived and worked alongside the water were accustomed to seeing it rise and fall, but they were ill-prepared for the disaster that befell them on June 9, 1972.
The trouble blew in with an air mass from the east. It met the Black Hills, pushed upward, cooled, destabilized, and developed into thunderstorms. The high-altitude winds were too weak to move the clouds, so the storms hovered where they formed.
And the rain began to fall.
It started in the afternoon and continued into the night. In the Rapid Creek watershed, most of the rain fell in a 10-mile stretch between the Pactola Reservoir and Rapid City. Some locations received up to 12 inches. Further north near Nemo, along Boxelder Creek, 15 inches of rain fell in six hours.
Rainwater ran through gullies, gulches and ravines, collected in creeks, and roared inexorably downstream. Multiple locations in the Black Hills were affected, but Rapid City was especially vulnerable with its thousands of people living, working and driving in close proximity to Rapid Creek.
As the evening wore on, flash-flood warnings were issued, and people prepared for high water. But as Rapid City Mayor Don Barnett later recalled, nobody comprehended the full extent of the “monster flood” that was bearing down on the city.
During the last few nighttime hours of June 9, an avalanche of water surged through the city, and the Canyon Lake dam ruptured around 10:45 p.m. A gauge above the lake recorded the creek’s rise of 13 feet in four hours. Within that span, there was a burst of nearly 4 feet in 15 minutes.
People in the floodplain suffered shockingly abrupt changes of fortune. Many described a sudden “wall of water” that threw their world into chaos.
The flood swept up propane tanks that exploded as they rocketed down the creek. Whole houses came loose from their foundations and careened downstream, colliding with trailer homes and smashing into bridges where thickets of debris piled high. Drivers on streets near the creek found themselves afloat.
Some people rode out the flood on rooftops or floating objects. Others clung to trees for several hours as water rushed around them. Many were drowned or crushed by the countless items hurtling down the creek.
After it was over, authorities counted 238 deaths, 3,000 injuries, 1,335 homes ruined, 5,000 vehicles destroyed, 15 bridges washed out or damaged beyond repair, and $165 million worth of total devastation. The flood still ranks among the deadliest and most destructive in U.S. history.
The catastrophe exposed numerous problems in flood preparations and planning, including the mistake of allowing so much development along Rapid Creek. There had only been four warning sirens in city limits, none of which was used during the flood. Shortcomings in the National Weather Service’s organizational structure, technology, and warning systems were also exposed. Those and other problems were addressed over time — most noticeably with a decision to forbid rebuilding in the floodplain, leading to the greenway and recreational path that parallel the creek today.
Meanwhile, the actions of the Institute of Atmospheric Sciences at the South Dakota School of Mines & Technology in Rapid City have remained controversial. That spring before the flood, the institute had been “cloud seeding” — spreading airborne material to serve as nuclei for condensation, with the hope of causing rain. The institute flew two flights on the afternoon of June 9, 1972, and dumped powdered salt into clouds. Later scientific reviews said there was no evidence that cloud-seeding caused the flood or contributed to its severity, but the findings did little to allay popular suspicions.
Fifty years have now passed since the flood, and although many stories have been told publicly, many more live only in the memories of survivors.
That's why Rapid City photographer Johnny Sundby asked me to collaborate with him on a coffee-table book featuring portraits and stories of flood survivors. In addition to working on the book, Johnny agreed to let me capture audio and video of the interviews. At SDPB, several colleagues and I have turned those recordings into an episodic podcast and a video documentary.
With each project, we have tried to act as a conduit for survivors’ stories, while acknowledging that the passage of five decades may have blurred some recollections. It was not our intent to compile an authoritative history of the flood, but rather to preserve tales of survival, as told by the people who lived them.
We hope the stories stand as testaments to the deadly and destructive power of nature, to the importance of prior warnings and floodplain management, and to the resilience that so many people showed while “Surviving the ’72 Flood.”
Where to read, listen and watch
The book: Available in Black Hills-area bookstores, from Johnny Sundby Photography and at SethTupper.com.
The podcast: Online at SurvivingThe72flood.com, and all popular podcast platforms.
Public screening, Wednesday, June 8, 6:30 p.m. Mountain, The Journey Museum & Learning Center, 222 New York St, Rapid City
Broadcast premiere Thursday, June 9, 9 p.m. Central, 8 Mountain, SDPB1-TV
Online at SDPB.org/watch and on the PBS Video app.
All things flood: SurvivingThe72Flood.com, SDPB’s comprehensive page commemorating 50 years since the Black Hills Flood. Featuring stories, audio excerpts, the SDPB documentary, an interactive flood map, and more.