Run-off Data

After a massive snowpack this winter and faced with a big run-off, a lot of folks are wondering when our freestone rivers are going to fish. Well, no one really knows for sure. But we do know where flows need to be for things to start fishing and we have some data to look at to make an educated guess. A general rule is when flows are dropping and the rivers are greening up the Flathead starts to fish around 25k, the lower Clark Fork around 15k and the Blackfoot around 5k. Granted these flows are still high and you need to know how to row like hell and employ high water tactics but these are flows that you can start to think about making a go of it.  Again, as long as flows are on the drop and there is a couple feet of visibility these numbers are in the ball park. Of course there are always exceptions to the norm.

Looking at the graphs here from a couple big snowpack years can give a little insight to what’s in-store. We all remember the legendary winter of 96/97. I was snorkeling the Big Mountain so I remember it well. And the winter of 2011 with the huge flows that followed, we remember that too(big browns on wire worms on the Missouri). The thing to note here is how much longer 2011 took to come down to acceptable flows than 97(97 was a bigger snowpack). 2011 had a ton of late spring and early summer rain that prolonged the run-off. So what’s the deal? Tons of rain will likley produce graphs like 2011 and a dry-ish spring and early summer will likley produce graphs like 97. Or not, Just some guess work and nonsense to ponder…

Run-off 1997

Run-off 2011

Jason Lanier

Owner/Outfitter at Bigfork Anglers Fly Shop
Jason is looking forward to fall hatches and cooler weather. Meanwhile he has been enjoying hopper fishing, cold lite beers, and swimming in the Flathead Lake.

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2018-05-18T00:34:45+00:00 May 17th, 2018|

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