Piles of trash have started showing up in local creeks, sparking concern the debris will spill into the Bay once the rain touches down on Thursday.
In Contra Costa County, debris and trash -- including an abandoned shopping cart -- can be seen along Grayson Creek. County officials said they will not clean it up because it is not stopping the flow of the creek.
More debris was found a mile up the stream in the unincorporated part of Pacheco.
"They should clean it more often if there is an El Niño,"
The filth is what worries residents like Steve Porter, who is concerned the debris will spill into Suisun Bay if the rainy season is anything like it was two years ago.
"I don't know if it's toxic or not," Porter said. "I don't know what's in there."
Alison Knapp with the Contra Costa County Public Works Department said crews maintains over 600 miles of roadway and 75 miles of flood control channels and creeks.
"What we do is we try to collect the debris," Knapp said.
Knapp said the department has received phone calls regarding the debris.
"The public have been very, very helpful," Knapp said. "So I have to look into it."
The trash downstream was cleaned up late Wednesday afternoon.