Big Chico Creek turned chocolate brown earlier this week after a light May 12 rain washed vegetation and eroding bank sediment from the Park Fire burn scar into the water. Today the water look somewhat clearer.
Environmental studies professor Mark Stemen said the wash-off has environmental benefits, but also poses potential danger.
“We should be seeing this happen for a while,” Stemen said. The dry weather that followed rain “freed up much more sedimentation.”
Some of the sedimentation “will end up in the creek and provide good sediment for spawning.” But if there’s too much, he warned, “it could suffocate [salmon] eggs. One of the things that’s really striking is how much of our watershed has burned and destabilized the sediment.”
Big Chico Creek provides crucial habitat for several runs of Chinook salmon.
Councilmember Addison Winslow said the runoff points to a potential problem: The threat of flooding from the Five Mile Recreation Area, where a dam diverts water to the Lindo Channel and provides flood protection for the City of Chico.
Winslow posted videos on social media when the creek turned chocolaty and noted in comments to ChicoSol that it’s been “decades since the [Five Mile Basin] has been properly maintained” because of sediment build-up. Winslow also noted that Butte County Public Works has been taking maintenance steps, especially since the Park Fire.
The Park Fire burned 429,603 acres last summer in Butte and Tehama counties, starting off Upper Park Road and reaching into the Big Chico Creek Ecological Reserve.
Leslie Layton is editor of ChicoSol.
Maintenance of these structures, like roadways, is always a challenge, and necessity. Take Chico’s urban streets for example. They have been budgeted just 20% of what was needed just to maintain existing streets. Basically budgeted to be 80% unsustainable. And look at the results evident in lost car parts. You can feel the damage that caused after several decades of neglect. It is like reading the message with your bottom sending messages up your spine. But back to our flood control system, it should also be managed for groundwater recharge. If THAT is being done it would be great to hear about. Perhaps in an article in ChicoSol.