Post by commonsense on Mar 15, 2010 22:57:34 GMT -6
I have wanted to help clear up some miss-information about the water levels at Lizard Lake. I am new to the forum and have not attended any meetings so this may have already been cleared up. If so, please disregard my ramblings for the next few paragraphs. I enjoy being able to communicate in this type of forum because no one can tell me to be quite if I start rambling which I may very well do as the answer to this involves a lot of math and biology, both things I had majored in but never graduated in because I never saw the real life application of them, and now here I am, proving myself wrong.
I see a lot of people seem upset that the DNR stated that the water level after the project would be returned to 1 ft. lower than the high water mark, commonly called the Ordinary High Water Level, or OHWL. Keep in mind that the OHWL of the lake is just that, the ordinary high water level as determined by the average high water level over a period of time as established by the fluctuations of water and indicated by physical characteristics of the lake. That is the technical version (that was paraphrased from the US Coast Guard definition), the layman's version is like this: The ordinary high water level is the average level of high water, flood water if you will, during times OF high water. The lake is not normally at the OHWL, it is mostly below that level, but occasionally above.
When they say that they will return the level to 1' below the OHWL, it could be assumed that just by reading the words as written, they will RETURN THE WATER LEVEL, not lower or raise the water level. If you research the OHWL of Lizard you will find that it is at 1188.63 M.L.S. (mean sea level). According to my internet research, there is an "X" on the southwest wing-wall of the outlet that is at 1190.45 M.S.L. Therefore the OHWL is 1.82 ft. below that "X".
Having never seen the "X" that they reference, it is impossible for me to sit at my computer and tell you the overflow level and therefore the lake level when it is level at the spillway. Keep in mind that the lake level when level with the spillway will be BELOW the OHWL that they reference, by how much can be determined by finding the "X".
For reference at a lake near Lizard that people of this forum may be failure with, as according to my research, North Twin Lake shows a OHWL as being set at 1.3 ft. above the crest of the spillway/outlet or at elevation 1215.54 M.S.L. That means that when the lake level at North Twin Lake is at/even with the spillway, no water is being discharged, and the lake is level which is due to that annoying constant, Gravity, it is at 1.3 ft. below the high water mark. This is what people commonly refer to as "normal pool".
"Normal Pool" on Lizard is therefore somewhere below the OHWL. With the information that I have found and what I have read here, it appears that people believe that the OHWL is at the spillway level, but they would be wrong. OHWL is alway above the normal standing pool of the water body.
If someone would find the "X" and measure to the top of the overflow, or where the water level would be when level with, but not flowing over the structure, I would be able to compute the water level above that overflow point. This is all assuming that there is still the "X" and it can be located. The next option is to just take an elevation reading and subtract the difference from that height at a steady elevation to the overflow level to get your "normal pool" and then take that and subtract the stated OHWL of 1188.63 giving you the OHWL above the spillway, similar to reference of North Twin Lake.
Going back to just reading the statement for it's face value as "the project would be returned to 1 ft. lower than the high water mark", one could assume that the overflow is at 1187.63 M.S.L.
At this point, if anyone is still reading and following, I applaud your effort!!!
I see a lot of people seem upset that the DNR stated that the water level after the project would be returned to 1 ft. lower than the high water mark, commonly called the Ordinary High Water Level, or OHWL. Keep in mind that the OHWL of the lake is just that, the ordinary high water level as determined by the average high water level over a period of time as established by the fluctuations of water and indicated by physical characteristics of the lake. That is the technical version (that was paraphrased from the US Coast Guard definition), the layman's version is like this: The ordinary high water level is the average level of high water, flood water if you will, during times OF high water. The lake is not normally at the OHWL, it is mostly below that level, but occasionally above.
When they say that they will return the level to 1' below the OHWL, it could be assumed that just by reading the words as written, they will RETURN THE WATER LEVEL, not lower or raise the water level. If you research the OHWL of Lizard you will find that it is at 1188.63 M.L.S. (mean sea level). According to my internet research, there is an "X" on the southwest wing-wall of the outlet that is at 1190.45 M.S.L. Therefore the OHWL is 1.82 ft. below that "X".
Having never seen the "X" that they reference, it is impossible for me to sit at my computer and tell you the overflow level and therefore the lake level when it is level at the spillway. Keep in mind that the lake level when level with the spillway will be BELOW the OHWL that they reference, by how much can be determined by finding the "X".
For reference at a lake near Lizard that people of this forum may be failure with, as according to my research, North Twin Lake shows a OHWL as being set at 1.3 ft. above the crest of the spillway/outlet or at elevation 1215.54 M.S.L. That means that when the lake level at North Twin Lake is at/even with the spillway, no water is being discharged, and the lake is level which is due to that annoying constant, Gravity, it is at 1.3 ft. below the high water mark. This is what people commonly refer to as "normal pool".
"Normal Pool" on Lizard is therefore somewhere below the OHWL. With the information that I have found and what I have read here, it appears that people believe that the OHWL is at the spillway level, but they would be wrong. OHWL is alway above the normal standing pool of the water body.
If someone would find the "X" and measure to the top of the overflow, or where the water level would be when level with, but not flowing over the structure, I would be able to compute the water level above that overflow point. This is all assuming that there is still the "X" and it can be located. The next option is to just take an elevation reading and subtract the difference from that height at a steady elevation to the overflow level to get your "normal pool" and then take that and subtract the stated OHWL of 1188.63 giving you the OHWL above the spillway, similar to reference of North Twin Lake.
Going back to just reading the statement for it's face value as "the project would be returned to 1 ft. lower than the high water mark", one could assume that the overflow is at 1187.63 M.S.L.
At this point, if anyone is still reading and following, I applaud your effort!!!