Map of camera placements as they were collected: https://www.google.com/maps/d/edit?mid=1rMMqElwDrDyP-kjr4Mj6fzcuVzDrIvw&usp=sharing
Timelapse videos from 1/19 to 1/29
I returned to the Klamath reservoirs this past Monday with Dan to find Iron Gate much the same as I left it and Copco completely gone! What an exciting development. I was hollering as I drove down the steep grade into Copco Cove and our first camera placement.
It's really really actually happening.
Dan ponders a new river.
We placed the CP01 camera just upstream of Copco dam looking upstream at the large meanders.
The channel banks here were shallow and low grade and much of the low-lying sediment plane was still saturated. Looking across the river from the CP01 placement, it was possible to see a few bank failures. These failures seemed to be associated with a tributary that went entirely subsurface and was springing out of the banks. Note the water flowing out of the bank in the photo and video below while the tributary has no overland flow.
As we moved upstream to the rest of our camera placements I was a little disheartened to discover that the active channel was not visible in any of them. Still, as we'll see below, I am very excited about where we placed them the second time around.
CP02 now looks downstream on a huge bank on an outside bend that is actively crumbling into the channel.
Note the slab failures breaking off the bank and failure debris on bank toe. Note also the tension crack on the right side of the image and the channel attacking the left end of the bank. The bank might be 15 meters high from a visual estimate.
Another large cutbank is visible in CP03's new placement
Note the circular cracking present on both sides of the channel. A similar appearance can be seen developing in the CP03 Timelapse video and it seems to be caused by a slow moving (timescale of hours - days) creeping of the banks into the channel. The banks seen in the CP03 Timelapse video have nearly identical circular cracking and appear to move almost like concrete. A particularly good example of this is shown below.
The new CP03 placement will be able to show us if these banks are still in motion. My guess is yes.
CP04 was moved to onto private property in the upper reaches of Copco reservoir.
Note again the circular, slumping creeping bank failures and high cutbank. The landowner noted that the channel was actively migrating into both corners seen in the photo. The landowner also noted that he had old maps of the river from before the dams went into place that showed the river through more or less the center of the valley. An alluvial deposit of gravel and cobbles could be seen where the landowner pointed out the map showed the historic channel.
Throughout the reach the channel was single-thread and meandered from valley wall to valley wall. The river appears to mostly be occupying its historic channel, which was visible on pre-removal bathymetry through much of the reservoir. The banks were mostly low and shallow angle and did not show signs of large failures with the exception of 3-4 large cutbanks as seen in the photos above. Several small tributaries enter the Copco reach and all went completely subsurface before connecting with the river. No knickpoint was observed in the reach.
This trip was simply breathtaking and I cannot wait to go down again on the 12th to see what has developed. Iron Gate reservoir may well be gone by then too.
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