E.coli bacteria levels have already dropped substantially in the South Yuba River, since a yellow plume, or sediment, was discovered last Friday that affected the color of the water between the town of Washington and Englebright Lake. Nevada County Environmental Health Director, Amy Irani says the “mpn”, or coliform count, has dropped from 816, to 16. But a no-swimming advisory remains in effect…

Toxic metal testing might be linked with all the mining activities that have occurred on the river throughout history. But Irani says that doesn’t necessarily mean there’s any connection to the plume. Meanwhile, the yellow color is already barely detectable, if at all, including at the state park at Bridgeport…

E.coli bacteria can be created by fecal matter, but Irani says there’s no conclusion, so far, on whether that was the cause. It’s also unknown if the E.coli is correlated with the plume.