As storms intensify, special boxes help keep trash from flowing into Bay Area waters
Climate change is triggering more frequent and intense storms as well as flooding. The more extreme the storm, the more trash and pollutants end up in our oceans, rivers, and streams.
Now a real-life buried treasure – known as a Debris Separating Baffle Box - is seeking to trap the trash before it pollutes critical Bay Area waters, and just in time for the next series of atmospheric rivers.
CBS News Bay Area got to see an installation of one of these structures at Bay Point. Professional Civil Engineer John Stiver is a Stormwater consultant at Contech Engineered Solutions. He explained what ends up in our local waterways is simply mind-boggling.
"We see chunks of concrete, we see basketballs, we see railroad ties, other things that you'll see floating out in the Delta and out in the Bay," remarked Stiver.
These baffle boxes offer a solution.
Two months ago, Contra Costa County installed a 4th large, full trash capture device on Willow Pass Road at Alves Lane. The crew excavated and shored up a massive hold into which a 40-ton structure was carefully placed and positioned.
The structure is impressive. Inside of it, a series of chambers, filters, and cages that divert, capture, and hold any trash and debris that will be carried via stormwater runoff into the drainage system. The baffle box captures more than large pieces of trash.
"We're capturing hydrocarbons, oil, and grease that comes off the street. We're also capturing fine sediment particulates," explained Stiver.
"We know that the trash will be caught before it gets to the bay," said Michelle Mancuso, Senior Watershed Management Planning Specialist with the Contra Costa County Watershed Program.
Mancuso noted how there are many reasons why communities don't want to have trash in their creeks, rivers, streams or bay.
"It damages our water quality. It hurts any organisms, the fish that live in the water. It is damaging to people. It can spread viruses or bacteria or create less oxygen in the water, which ultimately hurts humans and human health," explained the specialist.
By July 2025, certain municipal stormwater systems in California must install structures like these to prevent trash from entering and polluting waterways.
Caltrans contributed $1.6 million for the Bay Point project.
The baffle box is now underground and not visible. But some manholes are. These are used to access the device when it is full of trash and needs emptying.
Seven-year-old Sammy Jimenez and his mother Adele came out of their home to watch the installation. Both of them approved.
"It collects all the garbage," said Sammy.
"Sounds like a good plan," added his mom.