Have you ever wondered what "Specific conductance, water, unfiltered, microsiemens per...:

[Aden]

I look at the USGS gauge at little falls as a guide for accessing the river within my personal limitations of depth and flow.  But, I have always wondered of what use is the graph at the bottom of the page.  http://waterdata.usgs.gov/md/nwis/uv/?site_no=01646500

I found this site that I feel explains what the data means: http://www.ourlake.org/html/specific_conductivity.html

So, how does this apply to good or bad fishing conditions.  The part that caught my eye was how much salinity is in the water.  I also construe that the higher the conductance the clearer the water or at least the water has less junk in it.  

I would rather be out fishing but the rain showed up on my days off (of course)

[Miles]

Aden,

There used to be some other parameters on the LF gauge, including turbidity, which is a more direct measure of junk in the water. A while back the USGS put up a notice that those parameters were going to be cut for budgetary reasons; I thought I emailed the group about it, but can't find that email, so maybe I didn't. I know I talked to Dan about bringing it up at Beer Tie, but I guess we never got around to it. 

Anyway, if you go to the Potomac gauge at Difficult Run, you see the full suite of parameters, including turbidity: http://waterdata.usgs.gov/usa/nwis/uv?01646000

I made this graph by combining gauge height, specific conductance, and turbidity, and it ends up being pretty busy: you can see that there is a relationship between the three, but it's not a perfect correlation. Specific conductance is a reasonably good indicator of junk in the water, but gauge height is also pretty good. High water = dirty water.

I don't think the salinity level matters quite as much as turbidity to our fishing. I think the range on salinity is always going to be something the fish can deal with.

Maybe with our new public policy interest, we can see about getting turbidity added back to the LF gauge.

-Miles

[Aden]

Thanks Miles. That clears things up so to speak.