The meteorologists are calling for “aerial flooding” and “atmospheric rivers”…which in layman’s terms means HUGE STORMS! All of Northern California is drenched right now! Please read the following information to learn how this series of storms will affect the Coloma-Lotus Valley and the South Fork of the American River region.
This was contributed by Bill Center representing Camp Lotus and Dominic Pugliese representing Ponderosa Resort:
The Thursday 2:00 update from CNRFC shows a very slight drop in the projected South Fork peak flow from this morning, to around 26,000 cfs (cubic feet per second) at Chili Bar. This storm looks to me very much like the storm leading to the December 31 2005 flood, which was about 40,000 cfs.
Caution recommends that everyone along the river remove anything that can float or be swept away that is below the level of the 1995 flood. If you weren’t here then ask a neighbor. The 1995 flood was within a couple of vertical inches at Camp Lotus of the levels of the 1980, 1982 & 1986 floods. The 1997 flood, about twice the volume, was 7 feet vertically higher that the other 4. With virtually no snow up in the Sierra we are not in a 1997 South Fork situation, but the intensity of the rainfall predicted on Saturday into Sunday morning will cause a rapid rise of all local creeks and the South Fork, much of it happening in the dark and in pouring rain. So get ready early and be safe.
For folks interested in tracking the peak, and knowing about when it will reach the Coloma-Lotus area, here are some things I’ve learned. At flows above 20,000cfs travel time from Chili Bar to Lotus is an hour or less. So what you are seeing at the Chili Bar gage will get to Lotus no more than an hour later.
It is also worth looking at Dreamflows to see the flow below Slab Creek Dam, listed under real time flows, South Fork American. Slab Creek Dam will probably start to spill sometime Friday and if not then certainly on Saturday (right now the flow is 35cfs). Rock Creek is the major tributary that comes in between Slab Creek Dam and Chili Bar, and it will probably be contributing above 5000 cfs at the peak, with White Rock powerhouse putting in another 3000+, but in floods the South Fork’s major flow spills over Slab Creek Dam, and so looking up there gives another hour lead time for the flow shown at Chili Bar. Looking even further upstream at Kyburz gives the longest look ahead for the peak but gives less information about the magnitude.
To see a live feed and a rivers eye view of the storm, please visit the live cam brought to you by local business, the American River Resort. http://american-river-resort.raftingcalifornia.org/
Otherwise stay safe, warm and as dry as possible. It is really coming down right now, but the forecast should improve by mid-week. Hope to see you all at Christmas in Coloma held at the Marshall Gold Discovery State Historic Park next weekend, Dec. 8-9!