SACRAMENTO -- Certain areas along the American and Sacramento river are listed in the high category for dangerous bacteria.
Among them is Tiscornia Beach near Discovery Park.
Cool water and a warm sun Thursday afternoon made for perfect conditions for a day on the river.
"It's nice and quiet. That's what we all needed and let the kids burn off some energy," visitor Sherree Bagshaw said.
But it is what's invisible to the eye that's causing concern.
The California State Water Resources Control Board reports higher than usual levels of E. coli in parts of the river.
Officials say most of the E. coli in the water comes from bird feces.
"Birds like to congregate in the same places people like to congregate," assistant executive director Adam Laputz said.
That's why experts believe places like Tiscornia Beach and Discovery Park may have higher levels.
But with so much snowmelt, CBS13 asked if that would help disperse the bacteria.
"There's a lot of factors that need to be considered. And that's just one of them," Laputz said.
Laputz says it's still too early to tell, as the flow of information is as murky as the water. But the answer may just be a drop away.
"Right now, we're preparing and collecting samples and making sure we're at least learning from this time," Laputz said,
Water Board crews sample different parts of the Sacramento and American rivers weekly. They post their results, here.
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