Walnut Grove Dam is under Construction in Arizona.
Arizona’s Worst Disaster by Jim Liggett is a book about the Walnut Grove Dam Disaster of 1890. Even today, it is the largest natural disaster in Arizona’s history. The dam was located on the Hassayampa River north of Wickenburg, Arizona, and was built to provide water for hydraulic mining and irrigation. At the time, Prescott, Arizona, was the capital of the Arizona Territory before it became a state in 1912.
The book recounts the story of the Walnut Grove Dam from conception to failure and its legal consequences. It includes colorful characters such as Henry Wickenburg, Buckey O’Neill, and Governor Alexander Brodie. Subsequent attempts to rebuild the dam and the fate of the Hassayampa River over the past century are included.
In the early morning of February 22, 1890, water was overtopping the dam by three feet when it finally gave way. The superintendent of the dam had a strong feeling this was going to happen, so he sent a rider downstream to warn people to get out of the canyon to higher ground. The story goes that the rider passed by a saloon purchased a bottle of whiskey, and never made it downstream to warn anyone. In the end, it was estimated that 70 to 100 people lost their lives as the wall of water swept through the canyon toward Wickenburg.
Professor Liggett’s research goes back to the time when the dam was proposed and how it was financed. At that time, many of the investors were from back East, and that meant selling interest into a water company so they could build the dam. As you read, you can see how people who knew nothing about the project were out hustling money for investment—not much different from today.
The dam’s purpose was to supply water for hydraulic mining downstream and irrigation. Gold mining was the flashpoint for investors, who were hoping to cash in on a large return. Gold strikes had abounded in the area, and the streambeds were plentiful with gold nuggets. The water company they were investing in was set to reap a nice return for supplying water to the goldfields.
As you read the book, you will see that what we take for granted today, as far as engineering and hydrology are concerned, was not present at that time. This led to a significant problem in the dam’s design, which, combined with the lack of historical information on water flows, ultimately failed.
Walnut Grove Reservoir.
When they first started building the dam, the structure was leaking so badly that fish were said to be swimming through it. They stopped construction and hired another engineer and construction company to rebuild it from the ground up. In the end, the dam was built to a height of 110 feet and, when filled, held back nine billion gallons of water. It was a reservoir where people were boating, fishing, and hunting. It was also short-lived.
John Wickenburg, the town’s owner, owned the Vulture Gold Mine at that time. It was rich in gold ore, and a large processing mill had been set up on the Hassayampa River to process the ore at a little town called Seymore, just downstream of Wickenburg. Seymore probably would have never existed without the mill, but in its heyday, it had over 200 residents, a saloon, and a laundry.
When the wall of water hit Wickenburg, it destroyed all the orchards and farmland John Wickenburg had along the river. At Seymore, the wall of water destroyed the gold processing mill and swept it downstream.
Arizona’s Worst Disaster.
Professor Liggett goes on to weave stories together about the losses incurred downstream and the people who lost everything. One story was about Bob Brow’s saloon, which had been washed away along with its safe and a barrel of whiskey. Twenty years later, a newspaper mentioned that the safe had never been found. Bob Brow went on to own the Palace Saloon in Wickenburg, which is still in operation today.
About the author: Jim Liggett graduated high school in Prescott, Arizona, attended Texas Tech University in Lubbock, and then went to Stanford, where he received his master’s and Ph.D. degrees in engineering. Later, Jim joined the faculty at Cornell University, where he remained for 35 years. After retiring, he returned to Wickenburg, Arizona, where he joined a hiking group and became interested in the Walnut Grove Dam. His book attempts to fill in a gap in the territorial history of Arizona since this significant and defining event is largely ignored in the history books.
To Purchase the book, go to Desert Roamer Press | Purchase Books
Submitted June 2021, Greg Hawk, Desert Roamer Press. Updated March 2025.
Also See:
Arizona – The Grand Canyon State
The Johnstown, Pennsylvania Flood of 1889
Vulture City, Arizona – Gold Mine Ghost Town