Note: the Las Conchas Fire Closure Order is still in effect and the burned area is closed to public entry. I have been assisting the Santa Fe National Forest with trail assessments and identifying hazard trees and have permission to enter the closed area.
Cañon de Valle looks to be the victim of bursting debris dams. High flows in the post-fire world move around the logs in a stream channel. At constriction points, the logs can interlock and form a dam. Water backs up behind the dam until the weight of the water breaks through the dam. The resulting flow can be many times the flow generated by runoff and the erosive power of the surge of water can gouge out many feet of stream channel in a short time. Places in the post-Las Conchas fire Cañon de Valle appear to have had stacked debris dams: when the uppermost dam broke, the flow surged to the lower dam and burst that one, resulting in incredibly high flow volumes.
The lower, road portion of the route up Cañon de Valle is totally unrecognizable. The surface is concealed by a jumble of boulders. Near the junction with the Perimeter Trail, the road is completely gone. The trail that heads up the canyon is alternately washed out and just eroded with deep ruts. The western 1.5 miles of the trail is in good shape.
Just above the highway, I think this is the road in Cañon de Valle. It's tough to tell where the road is under the rocks. The first three-quarter of a mile are like this. Makes for tough mountain biking, and hiking isn't much fun.
The high ground here is where the road and trail used to be. When the debris dams upstream broke, the water ponded here before it breached the old road.
The trail was on the slope at the left side of the photo. This is just below the stacked debris dams. Although I know this canyon very well, there are many spots that are so radically altered that I don't recognize the location.
Above is the post-Cerro Grande erosion channel in June 2005; below is the same location with the post-Las Conchas channel in November 2011.
After about two miles, the canyon is like it has always been.
Assessment: Like in Water Canyon, it may be time to move the trail onto the slope above the canyon floor. Lots of work, but crews may be available this summer to begin the reconstruction.