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Okay, so i've been following the river levels pretty steadily for the last couple years. I've always paid sole attention the the flow discharge. (cfm's) I've always judged this on how high the river is. Is there any advantage to looking at both??? Seems like they would be directly correlated as in the gauge height couldn't be high if the flow wasn't also high? Maybe I'm reading too much into it, but seems like just looking at one would be good enough? Any thoughts or which one does everyone look at
 

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when u say discharge are u talking about a river that is damed ?? if not i aways go by height and cfs if u know the river and been following the height and cfs then u get to know how the river fishes at x height and flow.
 

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if im bankin it i use the gauge ht. mostly because i float fish a lot. i can tell you how deep to fish to the inch in most northend river holes just by lookin at the gauge. if im fishing in a sled or DB i use the flow in cfs, it will determine my teminal tackle( how much lead) and or tactics anything you can figure out b4 you get to the river is an advantage imho. Mike
 

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Re: Gage Height vs. Flow Discharge???

I don't think it really matters which one you look at. As stated before. When you get to know a river by one or the other. Then you have a good idea of what the river is like by looking at which ever one you are comfortable with.
 

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That is some great info Tup:
 

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This subject gets me laughing every month at work. I'll explain why.
First off I work with Dams so flows is something we always watch, incoming and discharge. Once a month our Hydrologists go out and manually measure the flows in the rivers. Then they do some magic math which will give them a flow conversion, CFS to a new gauge height number. Once they have this new number they will program the formula into the web sites you all look at, Hydromet, NOAA, ect, for an updated CFS/G.H.
Now what makes me laugh is, I will be discharging the same amount for the entire month from the last time they updated. (Example 500cfs) and once they give me thier new numbers and we program it into our computors, all of a sudden it may say we are discharging 400cfs or maybe 600 cfs on the river gauges. Even though we never even change the position of our units or spill gates and our penstock flow meters still read 500cfs. But because the world goes by the these charts you all see on NOAA, ect. We must make the change at the Dams to keep the desired river target.

NOTE: The Dams I watch are in Idaho and we try to maintain set targets on flow discharges because of irrigation water orders and everything I've been rambling on about most likely don't help with your question.

So what I'm saying is. A certian gauge height/flow one day, maybe have a different flow the next with the same gauge height. :roll:
 

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i have noticed that b4 as well. ill be expecting a certain rock to be at a paticular height out of the water and its not. i realize they are not dead on accurate but they can get a guy dialed in pretty close b4 he leaves home. like someone else said if you learn a river and its flow/heights you have a bit of an advantage IMO. MIke
 

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Discharge and gage height are directly related. As the gage goes up or down, the discharge goes up or down correspondingly. So it doesn't matter which you go by. You just need to learn what discharge or gage height fishes best on the river you're interested in.

Sincerely,

Salmo g.
 

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Don't want to hijack the thread but I have to agree with Salmo g. - gauge height and stream discharge are directly related. Once a stage-discharge relationship is determined on a hard grade control (riffle or hard bottom run), stream discharge (cfs) can be very accurately predicted from gauge height. I find it rather hard to believe that hydrologists would go out each week and measure flow - probably at the same location, and their measurements would vary 20-25% from some constant.

ClearCreek
 

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Quill said:
This subject gets me laughing every month at work. I'll explain why.
First off I work with Dams so flows is something we always watch, incoming and discharge. Once a month our Hydrologists go out and manually measure the flows in the rivers. Then they do some magic math which will give them a flow conversion, CFS to a new gauge height number. Once they have this new number they will program the formula into the web sites you all look at, Hydromet, NOAA, ect, for an updated CFS/G.H.
Now what makes me laugh is, I will be discharging the same amount for the entire month from the last time they updated. (Example 500cfs) and once they give me thier new numbers and we program it into our computors, all of a sudden it may say we are discharging 400cfs or maybe 600 cfs on the river gauges. Even though we never even change the position of our units or spill gates and our penstock flow meters still read 500cfs. But because the world goes by the these charts you all see on NOAA, ect. We must make the change at the Dams to keep the desired river target.

NOTE: The Dams I watch are in Idaho and we try to maintain set targets on flow discharges because of irrigation water orders and everything I've been rambling on about most likely don't help with your question.

So what I'm saying is. A certian gauge height/flow one day, maybe have a different flow the next with the same gauge height. :roll:
So are you saying it is only relatively accurate ? But still are flow charts an indicator?
 

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The river I fish I also watch gage height and discharge doesn't have a dam so that is not in effect. I use the USGS site. I am trying to get to know what it looks like after rain, snow, and floods.
 

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I'LL Second Salmos reply! I use to keep a log book on all the rivers I fished and I would always add in the CFS/Height that listed. The only thing that is missing is water clarity, to bad they could put that on their websites....
 

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Yes the flows and gage height are directly related. The best way to descibe what I'm talking about is, if you ever look at a chart from Noaa or whomever and there just happens to be a sudden rise or drop on the chart. Not a slow change, but a sudden straight up or down on the chart. This is what I'm talking about when they make a calculation change.

Not always do you see a big change, as sometimes they will only adjust a couple cfs, and it does not need to have a Dam on it, just a gauging station. I do have to monitor 30+ gauging stations hourly when on duty and we get the call from the hydrologists to make our computor adjustments for the new calculations, so I see it at the time it happens, not that a person couldn't look at past flow charts.

Everyone said it best, to just know your river and use the gh/cfs as a reference to know where you stand.
 
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