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Monday, August 2, 2010

Yo-Yo Flows & "Other Hatch" Report

Since my last fly fishing "prime-time" report of late June, regulated flows have played an important part as to WHERE, WHEN, WHAT and HOW to fly fish the local Truckee waters. In addition to being aware of the inflows from Lake Tahoe, Prosser and Boca, other seasonal phenomena have to be accounted for; specifically water temperatures and the summer-time "raft hatch" on the Truckee river.
Throughout the month of July flows were unpredicatable. Initially the BT out of Lake Tahoe was at 70 cfs then progressively ramped-up to its current 331 cfs. The increase was welcomed because the flows were receding, but, the increase in water temps was not welcomed because the lake was inflowing from the surface.

We've been on the BT are early as 7 AM and leave around 1 PM. At the latter time water temperatures are subject to your location. I've recorded a 62 near Bronco creek & at the NV/CA border (image below), 64 at the "loop" and 66 along Glenshire at "Cat-House Hole". The other opportune time is to be on the water during the last hour of light. Then you'll see various-sized Caddis and Little Yellow Stones. Unfortunately there has not been a lot of rising trout. Lead is required. Below Grey's Creek Pancho briefly had on a very large Brown that effortlessly topedoed through a whitwater chute...breaking off a Crawfish pattern. Typically for the BT, the catch is small Rainbows & Browns in the 7"-11" range. One can get complacent; then you get a grab & solid hook-up for the bigger guys in the 16" plus ready.

About the "raft-hatch" is all about timing it; assuming you want to MISS IT. The upper river from below the dam to the River Ranch Lodge is quite a scene. It is almost like bumper-cars (...not to mention a lot of eye-candy); especially on week-ends. Times to avoid this hatch are from 11AM-6PM.
If venturing into the Canyon; the permited (50 rafts), "guided" whitewater trips' only ingress point is at the Boca (Little Truckee inflow) ; no earlier than 10 AM. The only egress point is at Floristan; no later than 5PM. Also, the rafters are NOT ALLOWED TO DISEMBARK. If you see such report them to Nevada county. Here's the earliest arrival timing; 10:30 AM the pocket-water above the Hirschdale bridge and 11:30 AM at Grey's Creek.
After Labor day week-end the "hatch" will subside substanially.
The yo-yo flows have also influenced the fly fishing on the LT. It had been at a low of 40 cfs for about a month. Then it was ramped up to as high as 240 cfs...then quickly down again guessed it, 40 cfs. Talk about an adjustment in tactics; from sight-fishing to use of lead and back to a spring-creek game of sight fishing. Nevertheless some quality trout have been netted. The range has been two Browns to 22"* and two Rainbows to 20"**. There are no numbers though; a good session with a client being 10 hook-ups and 5 lands. Most sessions are 1-3 landed. Unlike spring & early summer we're starting to see smallish 8"-12" Browns & Rainbows.

As far as bugs to anticpate; PMD, surpringly BWO's, Midges, smallish Caddis.
We are also anticipating the appearance of the Flavelina (Little Western Green Drake...sized 10-12)

*#16 CDC Biot PMD Comparadun and #20 Purple Coppper John

**#18 CDC Biot BWO Comparadun

August is a great time to venture to the North Fork of the Yuba. Here you will find cool mountain springs that generally provide the NFY with 10 degrees less water temps than the BT. The trout aren't huge, but, very willing. This is a classic "quick-action" river. Use of attractor dries in the #14-16 range and droppers in sized 16-20 will produce good numbers of wild rainbows. A large trout is 12-14"; most are 6"-9".

More of "north of Truckee" in future posts; mostly in the form of an "eye-candy" photo essay of opprotunities in this uncrowded area.

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