-My professional background is in hydrology, geomorphology, and fisheries habitat.  As part of my job, I design and construct LWD jams in streams and rivers -Running rivers is one of my free-time passions.  I hunt and fish on class II and III rivers and spend another 20 - 30 days a year running class IV and V whitewater throughout the Pacific Northwest and California. 

Greater-than or equal-to 2.0m (6.6’) and greater-than or equal-to 10cm (4”) diameter

When secondary forming factors are included in the analysis, LWD assists the formation and maintenance of 40% of all pools surveyed. 

Pools with LWD are often support a greater number of species

Site “N4”, the only channel-spanning jam, accounted for 60%  of the adult Chinook observed

Underwater video of adult spring Chinook salmon holding in a LWD cluster several days after it was constructed (Klickitat River Meadows Project, Site K1, Yakama Nation Fisheries Program

Underwater video of 3 adult spring Chinook salmon holding in a LWD cluster of natural origin

Photo is of a channel-spanning log on the EF Hood River.  This type of position increases risk to boaters. However, there was a sizeable pool upstream pool and plenty of space to portage on the right bank which 9 of 10 boaters did without much trouble. On this particular trip, one of the less-experienced members missed the eddy upstream and ended up flipping on the log and washed underneath.

Everyone should boat “Heads-up” – be conscious of what’s downstream, boat spacing, and available eddy space

Though this piece prevents running the rapid top-to-bottom, it is more of a nuisance than a hazard (there is a good pool above it and ample opportunity to scout) The habitat value of its present position is negligible, but the potential for this piece to serve a downstream ecological function is largely dependent on remaining intact

Nearly channel spanning contributes to greater hazard with a high flip potential at pictured flows This particular log can be passed on river-right, but the boater wasn’t paying close enough attention as they approached This is an ephemeral/temporary resting location and the log will wash out of pictured position

Here LWD combined with boulders create a convenient eddy in an otherwise busy/continuous reach

Much of it has to do with recruitment potential…where standing trees of sufficient size exist (not uncommon), they generally fall from such a height/distance that the trees break and the resulting pieces are easily transported (i.e. less likely to hang-up in the main channel) In this case, LWD has been strained-out by riparian trees at the downstream end of a bar and high-flow channel

The diagonal log interferes with approach to the meat of the drop, but not a deal-breaker

Undercuts tend to pose more of a hazard on most California rivers than LWD, however, there is always the potential for strainers In this case, a substantial log has been pinned in an undercut sufficiently long (at least 10 years according to my source) for the rapid to be named after it

A friend of mine front-surfing one of the most dependable surf-waves on the Stabler to High Bridge section (“the Upper”) of the Wind River The hydraulic is created by the interaction of the log and boulders in the bed of the river

The individual who made the post has made numerous anti-wood-in-streams posts over the past couple of years. Ironically, the poster zealously defended environmental extremist Dave Foreman (co-founder of “Earth First”) in a different thread

Since half (3 out of 6) of the questions I received in advance involved removal of wood, I contacted some colleagues at various jurisdictional agencies.

This channel-spanning log on the Wind River (~1/2 mi downstream of Stabler) was easy to float over at moderate flows and a straightforward drag/portage on river-left at lower flows There are several class IV+ rapids downstream that would be far worse places to have to deal with these logs.