Rather than give you some goofy math problem to try and cypher ---(sorry Maria, algebra equations make me shudder) here it is in English =
Call (573) 546-2502 -- You will get an electronic Voice answering, and asking you to press any key...
It will then give you a number for the level of the Saint Francis, at 72 Bridge, the Upper Put in.
For example it may say "5.3" Subtract 3 from 5.3 and you get 2.3 then x 15 = 34.5" which should more or less be similar to what the reading at D Bridge would read upon visual inspection. Another example = you call the guage # and it says "3.0" you subtract 3 from that and get 0 x 15 = 0" at D Bridge.
The other factors to consider are, * if Stouts Creek is pumping in a bunch of water, it is below the 72 Bridge Guage at Roselle and will not be shown by the Roselle Guage. The same with Turkey Creek, Mud Creek, etc.. This could mean that a lot of the River is higher than the Guage is reading (especially with Stouts Creek)
* Another factor, is that the Pool of water where the Guage is located below 72 Bridge can be affected by Pesky Beavers building a dam right where the fast water starts out of the gate on the Upper Saint. This can sometimes cause a false high reading at Roselle when there is nothing really in the River below 72 Bridge. That only happens when the Saint is really low and we are salivating for any spike. A spike in the guage without any real precipitation in the area (and the Saint has been low) could be the work of Gootch Nickels friends, the Pesky Beavers. After all that "splaining" the Auto Voice on the Guage will also give you a Preciptation level in Inches say "24.5 inches" that would be from the start of the year, so you would have had to have known the Precip level before the Rain to note how much they actually got there. There is already a link(MWA Page) under Missouri Paddling Information to Precipitation by hour and location along the Saint.
Quick Reference Guide for Roselle Guage and potential correlation for D Bridge :
3.0 = 0"
3.5 = 7.5" example = 3.5 - 3 = .5 x 15 = 7.5 "
4.0 = 15" example = 4.0 - 3 = 1 x 15 = 15"
4.5 = 22.5"
5.0 = 30"
5.5 = 37.5"
6.0 = 45" (bout 3" over D Bridge)
7.0 = 60" and on and on she Rises !!!
Although this is only intended as a <> sorta thang , it is usually quite close to hearing a guage reading on the Phone and correlating to actual D Bridge Levels. Good luck and hope that helps ... Seems like every year newer paddlers come along and this process has to be repeated, which is good. because it shows the sport is always attracting new paddlers. Freddie, the Geezer (Not to be confused with "Some Old Geezer" as that is Bilbo ! )