Hamilton City’s new levee stands up to major storms of 2023

U.S. Army Corps of Engineers Sacramento District
Published April 14, 2023

Rip rap installed in 2020 helps protect the riverbank beneath the Highway 32 bridge during recent atmospheric river storms.


The Hamilton City Phase 1 restoration area floods as intended during March rainstorms.


Hamilton City’s setback levee allows for the river to naturally flow into the floodplain.

In the past, residents of Hamilton City eyed the Sacramento River with uneasy wariness when facing a series of major rainstorms. Now, they can sleep a little more soundly, knowing the U.S. Army Corps of Engineers Sacramento District has helped reduce the likeliness of flooding.

Located 90 minutes north of Sacramento, Hamilton City has always been prone to flooding due to its location along the Sacramento River and reliance on an undersized stretch of earthen barrier called the J Levee. For decades, this non-engineered levee was the town’s only protection from the mighty Sacramento River.

In fact, the community has had to fight to stave off inundation during several extreme weather events, participating in extensive flood fighting efforts in 1983, 1986, 1995, 1997, and 1998 to avoid levee failure. The town’s residents have also had to evacuate six times in the past 20 years.

With this year’s relentless atmospheric rivers dropping record amounts of rain and snow, it’s likely Hamilton City would have faced a major catastrophe, but the worn out J Levee is gone, and a $93 million levee and restoration project now stands in its place.

It’s called the Hamilton City Flood Damage Reduction and Ecosystem Restoration project, and it’s the first of its kind in the nation. The project provides improved flood risk management and greater levee stability by widening the river channel during high water events.  This will also help the river reconnect to the natural floodplain and restore approximately 1,400 acres of native habitat between the levee and the Sacramento River.  

Margaret Engesser, project manager for the Hamilton City levee and restoration project, explained what makes the Hamilton City project exceptional.

“What makes it unique is that it’s one of the Corps’ first multipurpose projects, authorized for the purposes of flood risk management and ecosystem restoration,” said Engesser. “It includes 6.8 miles of setback levee that not only provides much-needed flood protection for Hamilton City but also restores nearly 1,400 acres of native riparian habitat.”

Instead of placing a levee right along the edge of a river, a setback levee is built away from the water, allowing the river to overflow its banks and fill in a large area of land before reaching the bank of the levee.

“It is performing exactly as it was intended to. The river spilled over the banks and into the floodplain up to the levee, and everything held secure,” said Engesser. “The project is a testament to the planning and execution of the Sacramento District and the local sponsor.”

Hamilton City Flood Damage Reduction & Ecosystem Restoration