Corbo- l have only been fly fishing a decade longer than you so l may not have learned anything new in the last ten years. So in that regard we are equals. In terms of experience with our Tn tailwaters though l guess i have about a fifty year headstart on figuring them out. Still may not have all the science right but l do catch a nice fish every once in a while. I was asked to write dome articles in Trout magazine on our tailwaters in the late 70s early eighties which sort of outlined the state of the sourhrrn tailwaters at that time if you wanted to get some historical perspective. The questions you pose and the mission or trek Madison is on are not dissimilar from mine or what any inquisitive flyfisherman would pursue. I have been a student for a long time myself
What makes this river tick? How can it be improved? Etc
The clinch has has a sulphur population that l have seen since the sixties. In the preweir days it was sparse and primarily found at major creek mouths and in the last miles above Clinton. Prior to the weir In the sixties Norris had 2-3 consequetive months of oxygen levels that could approach zero parts per million, no minimum flow regime and low water was far lower and much warmer than what we consider low water to be today. Midge and blackfly was the bulk of the trout diet the that could survive and prosper.
When the weir was built immediately after Tellico Dam issues and in response to TU and potential 404 litigation it was a new concept. It was not engineered as well as the subsequent South Holston weir but it did dramtically improve the yr round oxygen , water temperature and min flow--these improvements basically created an entirely new ecosystem in the river and led to the prolific emphemeralla hatchs on the river today. Also improved the caddis diversity ,although the black caddis was seen occasionally even in the water wasteland days in the sixties. Today twra biologists say the Clinch is the overall best tailwater for trout productivity in the region , a statement that l m not sure l agree with but l am
Glad it is doing well.
The Holston below Cherokee was viewed by Twra historically as a tailwater unsuited for trout as it suffered both high water temps and low dissolved oxygen periods even more dramatic than the clinch. Rather than build a weir at Cherokee TVA used vented turbine improvements and other reoxygenation processes to dramtically improve the river. The temp issue solved itself with a minimum flow regime and the previously undervalued impacts of inflow from springs and cave waters. Because of the higher ph and the influence of spring inflow in the cherokee tailwater it carried more natural benthos diversity than the clinch.
The south Holston also had a good ph. More diverse rubble rocks like the main holston and unlike the hard ledgerock of the clinch. It had colder discharge water from higher elevation lakes and dams and always had a strong and more diverse mayfly base populaion which exploded on the greenhouse effects of weir improvements there. The SH weir is a much better engineered and constructed weir than the clinch weir, which was thrown up hastily with inherent limiting factors as tomits long term viability . Those SH weir improvements created a greenhouse with ideal water and nutrients for the sulphurs and the population responded dramatically. With yhe food base improvements the trout mass exploded too.
So historical perspective is important to understand l think. You have seen John Thurman's name in these posts. John is retired from TVA but still does contract benthos surveys on every Tva tailwater on an annual basis l
Think. He and l have spent a lot of time fishing and bird hunting all over the country and l will say he knows more about the Clinch benthos than anybody. Sometimes he manages to catch a nice fish too.
If ypu really want to know more about these tailwater bug issues you need to go to a TU meeting where John is speaking and catch him afterwards or find him on the clinch river. Look for two english setters in the water and you will find John.
John has given many collection vials to fisherman on the river and asked them to collect bugs they think are unusual snd get them back
To him to ID. HE SAYS HE NEVER GETS THEM BACK.
I agree with Waterwolf assessment of his list above of the other mayfly species besides sulphurs that he has seen on the Clinch. He and l have discussed those finds many times as has Thurman and l and l will simply say again none of us has ever seen a BWO or BAETIS on the Clinch. There are several different sizes of the "sulfurs" In the clinch from 14 to 20 or even 22. Their colors vary too. Some may appear more green in color and could perhaps be mistaken for some other species. Having fished extensive bwo hatches elsewhere for many years l think l could ID A bwo but l am not a trained entomologist so who knows. I am confident Thurman could. It would be great if the BWO was on the Clinch . But l would not personally believe what you read on somebodys hatch chart or river map or web page until a qualified scientist confirmed a proper ID, and so far that hasn't happened. I think Purdue university is viewed as having a premier entomolgy department and the TVA samples Thurman and others have done have been periodically reviewed by Purdue folks so there is some backchecking there. In any event Whether there might be a tiny bwo population or not, it is pretty clear thst the presence of them is completely insignificant as a food source in the clinch given the year round mass if other nenthos. This doesntb mean a bwo fly pattern wouldnt catch some of the clinch fish. So if you want to fish a bwo have at it.
Last edited by Joe Congleton; 04-26-2013 at 03:40 PM..