Monday, March 14, 2011

Go With The Flow

I make it a habit to check the flows before I head out for a session. Occasionally (like today), it prevents me from taking a day off work when the river is practically unfishable. What a difference a day can make, yesterday we hit the canyon below Hirschdale (350cfs and perfect), the trophy section in Reno (100cfs and way too low), and west of downtown Reno (475cfs, a bit off colored but fishable). Today, the river blew out cresting at nearly 1,000cfs, too dangerous and too fast to effectively fish. A warm storm and an above average snow pack were the culprits.

Flows change where fish will hold, in cold water, fish prefer softer deeper runs and generally stay out of fast moving riffles. They tend to be concentrated and are often found stacked up on top of each other, holding tight to the seems. In the warmer summer months, they're looking for oxygenated water and ofter hold in heavier water such as the heads of pools or in riffles where they can enjoy both oxygen-rich and food-rich waters.

From February through June, water flows can be especially volatile on the Truckee. Material changes occur daily as well as intraday (between morning and night as the sun melts the snow pack). When cold snaps occur and flows drop, new waters open up. Conversely, when flows increase, fail safe holes can be blown out. The entire Truckee system is an awesome fishery, but depending on flows and seasons, certain sections fish better than others. Don't be afraid to hike or drive in search of good water, and always remember, don't be discourage by off-colored water; according to Ralph Cutter, this is one of the best opportunities to hook a big brown with something big and bright, like a goblin.

If you are curious where the gage stations are located, click on this map link. Generally speaking, as you head up river, the water gets lower and clearer, but beware, several creeks run through the canyon including Juniper, Grey and Bronco, all of which can flow high and be choked up with silt when storms come through. Also, on the NV side, flows can swing wildly for other reasons. Several diversions and weirs siphon off water from the river into ditches for irrigation and hydro power, some dump the water back in the river, others don't. Verdi and Mogul flows can be substantially lowered by these diversions.

Flows are everything on the special regulations section of the Little Truckee. Above Boca, the LT is a tail water fishery which flows at a constant 45 degrees year round as it's released out of the bottom of Stampede reservoir which is over 300ft deep. It's subject to some of the most significant changes in flows which can dramatically change the fishing conditions in an instant. Combine a water master who doesn't care and a minimum required flow of 32cfs and what do you get? You get flows that often change by 200% or 300% overnight. I've even been on the river a couple times when the water literally got shutoff for 10 or 20 minutes. Not only do rapid drops in flows kill insects vital to the fishery, but low flows (70cfs and below) often concentrate fish in a handful of deeper pools and runs which anglers mercilessly pound throughout the summer. I try to avoid the LT during these times. Generally speaking, when flows are above 100cfs, fish can be found fairly evenly distributed throughout most of the 3+ miles between Boca and Stampede. In case you're wondering, as of Sunday, the LT still couldn't be accessed by truck, at least, not unless you like digging.


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