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Gerry Romer
11-22-2008, 02:45 PM
I have a question about the elevation numbers on the TVA Reservoir Information web page. Below the Discharge Schedule there's a list of "Observed" measurements. The first column in the Observed panel is headed "Upstream Elevation" and the second column is headed "Downstream Elevation". Assuming that the "Upstream" figure represents the impounded water level, my question is this: Where exactly is the "Downstream" level measured?

Is the water measured at the base of the dam or some unspecified distance downstream from the face of the dam?

In the case of Norris, for example, today's chart shows a downstream elevation of 820.78 (feet above mean sea level) immediately prior to generation, and a measurement of 824.61 (feet above mean sea level) at the height of generation. According to yesterday's historical data it will take between six and seven hours for the water level to return to near 820.78 --- where?:confused:

I understand this is downstream from Norris Lake, but how far downstream? I'm having a hard time believing that it takes 7 hours for the water at the base of the dam to completely fall out. (Of course I've never stuck around to see how long it takes 'cause I usually bug out and head down to the jail when the siren blows.):smile:

If it is farther downstream, how much farther? A mile? a nautical mile? Does it really take 7 hours to clear out enough to cross the weir dam?

Gerry Romer

Grumpy
11-23-2008, 08:33 AM
There's an old gauging station about a mile below Center Hill Dam, ugh, that's all i know:redface:

Grumpy

Fishermansfly
11-23-2008, 11:41 AM
Happy Birthday! Wish I was out catching fish with you, but hey in turn I'll be out here throwing one in the back of the car ultimately catching a much slimier type of animal!

Happy Birthday your how many years young again?
~Your son!

Paula Begley
11-23-2008, 12:56 PM
The birthday status says he's 59, but I don't believe it. I'd say he entered the year wrong and it's off by 10. He can't be older than 49. :biggrin:

Happy Birthday, Gerry.

Paula

Worrgamesguy
11-23-2008, 04:39 PM
Happy birthday Gerry! Just so you know, I'll be getting you something for all you've done for me.

nvr2L8
11-23-2008, 04:40 PM
Happy Birtyday, old guy!!

And many, many more. Hope your lines are tight even if nothing else is.

billyspey
11-23-2008, 08:07 PM
man trying to get an answer to a question on this site than everyone starts on how old you are NO justice .. HAPPY BIRTHDAY GERRY !!!!!!!!!!!!!!!!!!
o by the way i don't have answer to your question

flynut
11-23-2008, 09:12 PM
I can only offer my own personal observations from my experience fishing the Caney Fork...but they have done me well over the past couple years...and I figure the same ideas would apply to other Tailwaters...

The water begins to rise at Happy Hollow roughly 2 hrs after generation begins...

At Betty's Island it's around 3 hrs...

And at Congo Bottoms its around 4 hrs...but don't misjudge this one b/c you can easily get stuck...

Now I don't claim to be an expert on how long it takes the water to fall, but based on trial and error from when I first started fishing the river, I've found that 6 hours is a good estimate. I think the water falls faster closer to the dam and slower the further downstream...

If I am wrong, please please please someone point out my mistake, as it will certainly allow for more fishing time in the future...

heyski
11-23-2008, 09:28 PM
The birthday status says he's 59, but I don't believe it. I'd say he entered the year wrong and it's off by 10. He can't be older than 49. :biggrin:

Happy Birthday, Gerry.

Paula

Do people on the internet age?

Hugh Hartsell
11-23-2008, 10:26 PM
Gerry,
Let me wish you a happy birthday first, and I'll give you my thoughts on the "downstream elevation" of each dam. When you're up close to one of the dams, look closely at the small section on one side that is a concrete corridor. There is usually a measuring devise along the side just as the concrete corridor ends. The water level for the downstream side is level in this area and that is where it is measured. Best wishes again for your birthday.
Hugh

David Knapp
11-24-2008, 12:02 AM
Happy Birthday Gerry! Hope you had a good one...

Gerry Romer
11-24-2008, 01:52 AM
Many thanks to everyone!! No I didn't catch any today but I gave it a try anyway. Fished Millers Island from about 1:00 pm to 6:00 pm with nary a single bite :frown:

Nevertheless, as the saying goes, a day attempting to fly fish is still better than a day raking leaves... or something like that.

On the "Downstream Elevation" thing, turns out both Brett and I emailed TVA for the particulars about 24 hours apart and we're both waiting for an official response.

Hugh, I should have known you'd have the most direct info... I'll check it out next time I make it up to the dam (almost made it today but I got side-tracked by Miller's Island this afternoon.

Again, thanks for the kind thoughts :biggrin:

Gerry

Fishermansfly
11-25-2008, 03:07 PM
http://i113.photobucket.com/albums/n209/fishermansfly/Untitled-1.jpg

A direct email in a quite timely fasion from TVA. Mr. Hartsell you never stop impressing me. However, both dad and I are puzzled on it taking 5 to seven hours to return to pre generation water levels! That seems rather inaccurate, but that's coming from being on the water and watching it fall out!

~Brett

MadisonBoats
11-28-2008, 11:47 AM
Gerry Romer

The avg base elevation of the river bottom is 818' at the dam's base. So, you can subtract this amount from the observed amount to get a good idea of the depth of the water.

Hope this helps.