Thursday July 17, 2025
CapRadio —
It’s a sunny weekday morning and Joshua Thomas is walking down a trail along the American River in Sacramento. Massive oak trees shade this trail on the south bank of the river near Watt Avenue.
He points to one that is hundreds of years old and named Odin. Thomas said it’s the largest tree on this stretch of the river.
“That tree is marked for removal,” Thomas said. “That’s where they’re going to put the access ramp.”
The Army Corps of Engineers is planning to remove that tree, he said, along with hundreds of others as part of a levee reinforcement project, called the American River Common Features Project.
This section of the project—upstream from Sacramento State’s campus—still needs approval from the Central Valley Flood Protection Board, which is voting on it Friday.
Contract 3B South is part of a larger project to reinforce vulnerable sections along the levee of the American River. 3B South is of particular concern to the American River Trees group because of the large equipment, large rocks and tree removal.Army Corps of Engineers
Thomas is part of American River Trees, which is urging the Corps to consider alternatives, like removing less trees and using smaller rock — the project calls for large, jagged rock called ‘riprap’ to line the levee. He says the rock will make the shoreline much less enticing for swimmers. He and other members of the group are concerned about the project destroying unrecoverable resources — like heritage oaks and other natural features.
“They’re kind of creating a homogenized Parkway—they have this ideal slope ratio and what the bank should look like,” Thomas said. “But that diversity not only fosters diversity of habitats and wildlife, you hear the birds, but also different experiences in the Parkway.”
“They’re going a bit overkill, and they are destroying permanent resources, like heritage oaks, really huge oak trees,” he said.
Not to mention the character of many swimming holes will totally change. He walks down to a spot on the river he frequents with his wife and young son. It’s perfect for wading in the summer, he said. And the best part of all: shade.
“It’s one of the few places in the [American River Parkway] I think that is completely shaded on a summer day,” he said. “You can be here and it can be 110 [degrees] out but you’re just completely in the shade.”
The concern about the loss of trees is one example of the tension between preservation groups and efforts to upgrade the state’s aging levee system.
Flood protection in the Sacramento region
According to the Army Corps of Engineers, Sacramento is one of the most flood-prone metropolitan areas in the country.
Hans Carota is one of the lead engineers on the project for the Corps. Standing at a swimming hole along the river near Larchmont Park, he points out the erosion that is already visibly happening on the bank. He grabs a handful of fine dirt. It seeps through his fingers.
“During a flood event, we’re expecting that this will quickly erode and undermine the levee and threaten the safety of the community behind the levee,” Carota said. “It’s critical that we construct this erosion protection to provide that safety to the community.”
According to the Army Corps, over 500,000 people in the Sacramento area are dependent on levees for protection. And if there’s a breach, there could be more than $60 billion in damages and hundreds of lives lost.
The Sacramento region is relying on the Folsom Dam, aging levees and weirs. This problem is not unique to this area. Advocates have urged the state to rethink its standards for the deteriorating levee system as climate change brings more intense storm patterns.
The problem with Folsom Dam is when it was built in the 1950s, they based it on the prior 50 years of flood history, Carota said. But after it was built, he said they noticed floods were much worse than they were anticipating.
“There was actually a tree ring study done in the 1990s that looked at tree rings going back as far as 1560,” he said. “What we realized when that analysis was done was that 50 year period our dam design was based on was the driest 50 year period in the last 400 some-odd years,” he said.
They thought they were prepared for that mega-flood that only comes around every 400 years, but it was more like 70 years, he said. “So a huge reduction in the level of protection,” he explained.
Proposed alternatives
Thomas, with American River Trees, says he’s not against flood protection — after all, he understands the risks having studied Sacramento’s flood control history at UC Davis.
“You are living basically in a bowl, surrounded by huge reservoirs of water—the mountain snowpacks,” Thomas said of living in the Sacramento Region. “And then you have these huge atmospheric storms that not only dump a lot of water but melt those snowpacks instantly.”
But he said the Army Corps could use less heavy machinery, cobblestone instead of riprap to cover the banks, and remove less trees.
Jeffrey Mount, founding director of the Center for Watershed Sciences at UC Davis, said trees cause two problems. One is they slow water down, creating more pressure on the levee. “Two is: trees fall and their root wads poke holes in the levee,” he said.
Engineers are all about following protocol to ensure the least amount of flood risk, he said.
“The engineer wants a perfectly smooth, trapezoidal channel that nothing interferes with the flow,” Mount said.
He says he feels for the local community, but the Army Corps has strict national standards they have to meet with these projects.
“Imagine if you’re doing a foundation for your house, there’s standards for that. If you’re doing earthquake engineering, there’s standards for that,” Mount said. “Now there’s some flexibility on how they get there.”
Carota says the riprap—24 to 30 inch sized rock—is needed to ensure the levees don’t erode. “Because of how powerful the floods are going to be that pass through here, that rock has to be that sized rock,” he said. He added that the area will be replanted and have a natural look again in a matter of years.
An example of revegetation after a levee reinforcement project along the American River near Elvas Avenue in East Sacramento.Courtesy of the Army Corps of Engineers
As for the trees in this area, he says the Corps has taken many steps to lessen the impacts, including a tree-by-tree assessment of the area. This area will look much different from the more barren stretch that was recently worked on closer to Sacramento State and Campus Commons, he said.
A map of trees being removed and preserved from the Army Corps of Engineers Environmental Impact Report.Army Corps of Engineers
According to the final Environmental Impact Report, “Approximately 515-540 trees are proposed for removal to enable construction [on the south bank near Watt Avenue], with 630-665 trees designated for avoidance and preservation.”
Still, many who frequent this area think more can be done.
Jeri Langham, a retired Sacramento State professor, leads birding groups around this area. On a recent morning, he and his group encountered 52 species of birds including a bald eagle and an osprey, he said.
“Taking out some of these great big heritage oaks is just a nightmare,” Langham said. “But they don’t care… ‘Army Corps of Ecosystem Destruction’ is my name for them.
Thomas with American River Trees is hoping the federal agency can modify its plans further and preserve the beauty so many locals enjoy.
He says if the project goes through, he’ll probably take his family to other areas along the river like Gristmill Recreation area, if it’s not too hot.
“Can’t really do that though on really hot days, when it’s like 110,” he said. “None of those areas are like this during the summer.”
According to Central Valley Flood Protection Board staff, the board will take public comment ahead of the vote at its Friday, July 18, meeting.