Simplified Version of Using the USGS River Gauges

 In another article here, I wrote a very detailed version of how to get all the information that you can possibly use from the US Geological Survey river gauges.  This will serve as the simplified version for those just starting out to use these gauges.

There are a lot of apps available these days for checking river levels, but they all get their info from the USGS gauges, and none of them that I've found have enough information to be as useful as the "real thing".  The USGS gauge pages are not as user friendly as the apps, and there is a learning curve to using them.  But the site is free, as is all the information in it, and once you get accustomed to using it, you will find it to be reasonably easy to get the info you want.  

First, what CAN you glean from the river gauges?  Most people who use them do so to check water levels and at most to see what the river has been doing for the last few days.  But if you know what to look for, you can find out exactly what the river is flowing and what it should normally be flowing, so you'll know whether it is higher or lower than normal.  You can see whether it has had a rise in the last few days, and if so how high that rise was and how fast it has been dropping.  Then, with remembering a few simple "rules of thumb", you can tell whether the river has enough water to float, whether it has too much water to float, what the river conditions will be, and even make a good guess on how clear or muddy it might be.  So here is how to begin to use the gauges.

The first step is to find the gauges on the internet.  For Missouri, the site is:

waterdata.usgs.gov/state/Missouri

Whatever state you are looking for, you just switch from Missouri to your state.

This should bring you to the opening page for Missouri.  On your smart phone, it will look like this:

From here you can go to other states if you wish, but otherwise just scroll down a bit on this page, and you will find a map of Missouri showing the streams of the state and all the gauges and their location:

This is one of the things which makes the USGS site less user friendly than the apps.  Since the streams aren't labeled, and neither are the counties, you need to know your geography to pick the gauges you want.  There are other ways to find the gauges, but they are even more cumbersome.  There is no search feature that I can find.  When you get to this map, you have to guess at where your gauge is, and click on gauges in that area until it comes up.  Your only other choice at this point is to set up a Favorites page with all the gauges you typically check, which in itself is cumbersome.  And if you're like me, you might be interested in gauges on streams all over the state, so your Favorites ends up being 75 gauges that you have to scroll through to find what you want.  I just wrote, again, to the USGS in their comments section to plead with them to fix this.

But this map does give you SOME instant information.  The colors of the gauges show whether that gauge is below or above normal flow. You can find a legend showing what the colors signify if you scroll down a bit farther below the map.

So you can zoom in with two fingers on the map (on your phone) to get to the area you want to check.  I'm zooming in on the Jacks Fork (fortunately, I've studied Ozark rivers long enough to know where they are on a map):

Here you can see the three gauges on the Jacks Fork (as well as the two on upper Current River above the Jacks Fork).  I'll click on the most upstream gauge on the Jacks Fork:

Now it gives you the name of the gauge, while showing with an orange circle that you've selected it.  It also gives you the present flow in cubic feet per second (82.7) and shows that this flow is in the normal range.  If you're sure that's the gauge you want, and if knowing the present flow in cfs isn't enough information, you click on the "View Monitoring location page".  This will take you to the actual page for the gauge, with all the information you might need:

This is the top of the page.  It does give you a choice of showing the past information on the graph below for 7 days (the default setting), 30 days, or 1 year.  The others can be interesting but all you need is the 7 day graph.  So leave it at 7 days, and scroll down the page to the graph:

This is the graph for what the river has done in the last 7 days, as far as the level in feet.  For the purposes of figuring out exactly what the conditions are now, it has limited use unless the river has recently had a rise.  Here, it shows that there was a rise a few days ago, but you have to look at the increments on the left side of the graph.  Note that they are fractions of a foot, not feet, so this rise happened to only be an inch or so, completely insignificant.  Otherwise the river has been steadily dropping.  If there was a real rise, it would look like this graph for upper Big River during this same time period:

Note that on this graph, the increments on the left are in feet, not fractions of a foot.  So you know that the river rose several feet at least.  Now note that there is a slider bar at the bottom of the graph.  The vertical line on the slider bar is ordinarily at the right end of the graph, showing the present level.  But you can slide it to the peak of the rise, and it will give you the level in feet across the upper part of the graph.  You can see here that the peak of the rise was 11.42 feet on the gauge.  Now I'll slide the bar over to a point before the rise began:

You can see that the river was at around 2.74 feet before the rise.  Do the math and it shows the river rose 8.68 feet.

The number of feet of rise is important.  We will discuss why later in the article.  But this tells us nothing about what river conditions are now except that it is dropping rather quickly after the peak of the rise a day and a half ago.  So after noting the rise in feet, we need to scroll down, because we are looking for a graph for the flow (discharge) in cubic feet per second.   Moving back to my Jacks Fork gauge page, by scrolling down, we come to this screen area:

You can see a "graph it" button to for "Discharge, cubic feet per second".  When you click on it, the screen changes to this:

There is one more important button to click; "Median day of year statistics--indication of normal levels". Clicking it and then scrolling back up to the graph, it will have changed to this:

It's now showing the discharge in cubic feet per second instead of the level in feet, and the series of horizontal gray lines show the median flow for each day.  So you can quickly tell how close the river is to normal for the time period--in this case, it has been above normal for the last 7 days.  

This is the real meat of the gauge, but there is one more thing to click on; "Show today's statistics".  Doing so will give you the exact figures for the date:

Note that it gives you the median, 25th (percentile), 75th (percentile), low, mean, and high.  The median is the flow at which 50% of the time the river has been flowing more water on this date, and 50% of the time less water.  It is the best approximation of normal flow for the date.  The mean is the average of all flows, and is actually useless for our purposes, because it is skewed upwards by the fact that any significant floods that have happened on this date are far higher than normal than the low flows are lower than normal.  At least one of the apps you can get shows the mean, none show the median, which is the MOST useful of these pieces of information.

The high is the highest flow ever recorded for this date, the low is the lowest ever recorded.  The 25th is the percentile at which 25% of the flows for the date were lower, and 75% higher.  The 75th is the percentile at which 75% of the flows were lower, 25% higher.  The USGS uses these two figures as the upper and lower limits of what is considered normal flow for the date.

Now you have all the information you need.  You have the present level in feet, and discharge in cubic feet per second.  You know if there has been a rise, and if so how high it was and how long ago it was, as well as how fast the river seems to be dropping.  You know the median flow for this date and that it is a good approximation of normal, so you know whether the river is low, high or close to normal.  So now you can put everything together as long as you remember the following rules of thumb:

1.  If the river may be low, and you need to know if it is too low to be floatable without a lot of dragging boats and scraping bottom, remember one key number--100 cubic feet per second.  On any stream in the Ozarks that can get too low for easy floating, 100 cfs is the absolute minimum for floating without a lot of dragging and scraping.  In our upper Jacks Fork example, the river is flowing 82.7 cfs and dropping, so you instantly know that if you float it, you're going to have to do some walking and you'll be scraping bottom a lot.  Note that you can also figure that anything under 50 cfs and there will be very few riffles that you can float cleanly and you'll be walking a lot of them.  Anything over 150 cfs and you'll have pretty easy floating unless you are terrible at reading water.  

Also, note that the median is only 45 cfs.  That tells you that the river here is NORMALLY too low to float this time of year.  A median of well over 100 cfs would tell you that it is normally floatable.

2.  If the river has had a rise and you want to know if it is still to high to float safely, a general rule of thumb is that a rise of less than one foot is generally not a problem; the river will be only a little bigger and faster than normal, and will probably still be fairly clear.  A rise of 1-2 feet, and it will be considerably faster and heavier water.  The consequences of mistakes can be more severe, and inexperienced paddlers should avoid it with that kind of rise, or at least float with other experienced paddlers who can guide them through the dangers.  The river will probably be murky and may be muddy.  A rise of 2-3 feet means very heavy current, with the consequences of mistakes possibly life-threatening; ONLY paddlers well equipped and experienced in such water should be on the river in these conditions.  The river will be muddy and may have some debris in it.  Over 3 feet of rise, and it should be off-limits to everyone.

Those simple rules of thumb should serve you well in understanding the gauges and knowing how to interpret the information.  There is a lot of other information to be found on the gauge pages, which I go into in the other river gauge article on this site.  But this will be enough to get you the information you usually need.  

 

  

 

  

Gravel in Ozark Streams--the Problems

 All of us who float, boat, and fish Ozark streams have noticed that our favorite waters seem to be getting shallower, with pools filling in and habitat degraded in some of the spots we fish.  There are constant calls to do something about this, most commonly from people convinced that we need to allow more gravel mining.  But is that true?  Nope.

Gravel is a part of the geology of the Ozarks.  The limestone and dolomite that make up much of the surface rock strata is weakly soluble in rainwater, and the water dissolves voids within and between the layers.  Chert forms in these spaces, and some formations also produce drusy quartz, the same mineral as chert—silicon dioxide—but in masses of crystals that form on the inside surfaces of the voids.  Silicon dioxide in either form is much harder than the matrix rock and remains on the surface as the limestone is dissolved and eroded away.  So all the streams have sources of gravel, though some flow through formations that produce more gravel than others.

Gravel erodes off the hillsides with heavy rain, into the hollows, creeks, and tributaries that feed the streams.  This has been going on since at least the last ice age, when glaciation occurred almost to the latitude of the Ozarks.  At the time of the greatest ice cover, the Ozarks was probably treeless except perhaps in small, sheltered areas, and when the ice began to melt, the climate was wet and erosion was rampant off the nearly bare hillsides.  The evidence of this is found in the thick layers of gravel beneath the topsoil in the bottomlands of the larger streams, gravel that has also been mined for many years, and which one can often see in the places where the stream is eroding a bank; there will be a layer of alluvial mud, and beneath it, near the normal water level, a layer of gravel.  If we think gravel is bad in the streams now, we should have seen it 10,000 years ago!  The valley bottoms were probably almost all gravel, with the streams running in braided channels through those extensive gravel beds.

Thousands of years of weathering and forest growth changed the streams and valley floors.  As trees and other plants covered the gravel bottoms, they trapped topsoil that built up in thick layers over the gravel.  The forests became old growth; big, widely spaced trees with native grasses growing beneath, maintained by natural and Native American set fires.  The growth held the gravel on the hillsides.  Gravel already in the stream channels was washed downstream and ground away until at the time of the first European settlers, there were many sections of streams flowing over bedrock bottoms, as reported by Schoolcraft and others.

But then came the great logging boom of the early 1900s.  The forests were cleared.  Brush grew and shaded out the grass.  Burning to remove the brush and “kill ticks” was common and widespread.  The gravel began a new cycle of erosion into the streams and tributaries.  In old photos from the period of the 1920s to 1940s, Ozark hillsides are covered in sparse, scraggly trees, with brush and a lot of bare ground, perfect for widespread erosion.

By the 1930s, the streams were probably in the worst shape they had ever been during historic times; not only from wholesale erosion, but from log drives and railroad tie rafts that destroyed banks, uprooted trees, and scoured the bottom of the stream in shallow water.  It took until the 1950s before the forests had grown back enough to provide some protection from erosion, but the native grasses that were best at stabilizing hillsides never returned, and gravel continued to enter the streams.  Logging, housing developments, clearing of hillsides for pasture, roads, and ATV and horse trails have proliferated over the watersheds, all contributing to more gravel in the hollows and tributaries. 

Most people would be surprised at the amount of gravel continually coming into the rivers.  I saw this firsthand many years ago.  There had been a massive rainstorm that was centered over one small area of Jefferson County through which Big River flowed.  The river got no rain upstream of this area, so the upper river didn’t rise.  Instead, it stayed normal until reaching this small area, where the massive rainstorm caused a rise beginning in this one section.  I floated from Mammoth Bridge to Brown’s Ford a couple weeks after the flood that ensued.  I could tell from the mudline on the vegetation at Mammoth that the river had only risen a few inches.  But the farther I went downstream, the higher the mudline was, until at the end of the float, 10 miles downstream, it had been 8 feet higher than normal.

Amazingly, at the mouth of every tiny creek and hollow there was a delta of gravel and even rocks up to the size of a basketball, and some of those deltas extended halfway across the river.  There had obviously been a massive amount of gravel coming down those wooded hollows into the river.  But in a usual flood, where high water coming from upstream would have scattered that gravel as it entered the already high river to the point where it was unnoticeable once the river dropped, it hadn’t gotten high enough upstream to move the gravel.

Crucially, huge rains like this are becoming more common with the changing climate.  It doesn’t matter whether the change is human-induced.  The fact is that huge floods are occurring at a greater frequency than they did throughout much of the 20^th Century.  They are often occurring almost back to back, with two or more floods within a very short period of time.  Examining the US Geological Survey records for the Sullivan gauge on the middle Meramec, you’ll find that from 1915 to 1970 there were six floods that exceeded 40,000 cubic feet per second, only two of which reached 60,000 cfs.  From 1970 to 2025, the same number of years, there have been 12 such floods, including a new record flood and six more floods over 60,000 cfs.  So there is more erosion occurring, which means more gravel in the streams.

But new gravel is not the sole reason, nor perhaps even the main reason, that the rivers appear to be getting shallower.  River channels are widening. 

The same volume of water will be deeper in a narrow channel than in a wider one, and narrow channels also increase the force and power of the water, making it better at scouring out pools and maintaining them at high water flows.

So why are the streams widening their channels?  It all starts with destabilized banks.  It is difficult for many people to understand, but while floods do the damage, stable stream banks lined with trees and vegetation are usually not susceptible to erosion in a typical flood.  The intertwined roots hold the bank together, and the flood’s power cannot find a weak spot to attack.  It takes a truly huge flood, or some kind of damage or change in the bank, to make it vulnerable to erosion. 

The most obvious cause of destabilized banks is landowners clearing the trees to water’s edge, removing the protection those tree roots furnish to the banks.  In the 60 plus years I’ve been fishing Big River and the Meramec, my two “home” streams, I’ve seen the river erode more than a hundred feet of some of those cleared banks.  In several places, I can show you where the erosion has removed an entire bottom field and the river is now up against a rocky hillside.  And invariably, where a bank like that is eroding, gravel is building up on the other side, which has become the inside of a bend.  You will see a gravel bar, then a zone of young trees, with progressively bigger trees the farther away you get from the river channel.  The river’s original bank with mature trees might be hundreds of feet behind those zones of growth.  Landowners see the damage, but by then it’s very difficult to fix.  The erosion must first be stopped, and that usually means hardening the bank with riprap rock (or, in the past, anything a landowner could get hold of, including old car bodies).  Some landowners have attempted to use just piles of big rocks at intervals along the bank, but this seldom works because the rock piles just cause much more turbulence in high water, and the river is likely to eat away the bottom surrounding them, leaving them as isolated rock mounds in the river. Covering an entire bank with riprap works better, but isn’t foolproof; there is one spot near my house on the Meramec where the river ended up eating out the bottom behind the lower end of a rip rap bank, leaving the line of rock as a submerged ridge in the middle of the river.

Once you succeed in stopping the erosion by hardening the bank, then you have to plant trees atop the bank to further stabilize the bottom field, and hope they survive long enough to be of a size to do the job.  Often, they do not.  It is an expensive, labor intensive, long term project.

Even if an entire bank isn’t gnawed away, changes in the flow regime caused by removing trees or just digging around in the bottom field behind the tree line can cause the river to widen and shallow.  One of my favorite places to catch smallmouth when I was a kid was a quarter mile long pool that was narrow, 4-7 feet deep throughout its length, flowing between alluvial banks lined with big trees, with old wood cover along the banks.  With the channel so narrow and confined within high banks, the upstream portion had enough current and depth to make it a perfect spot for smallmouth, with big, slick logs in 5-7 feet of water providing the cover for ambush points. 

I fished that pool for 15 years, and it remained completely unchanged the entire time.  And it was probably just as unchanged for many years before, because my dad told me he fished it when he was younger and it was always good.  Then, the landowner on one side cleared the trees off his side and began digging and selling topsoil out of the field behind where the trees had been.  It was not on the outside of a bend, so the current didn’t start cutting his bank away.  Instead, the next couple floods lowered the bank and allowed water to spread out over the bottomland where his digging had been.  The whole bottom field was eroded, the bank lowered into a gravel bar, and the upper half of the pool went from a narrow channel 5-7 feet deep to a wider channel from inches to 3 feet deep…all without the spot receiving more gravel.

So it becomes obvious that humans removing trees is a huge cause of bank erosion and widening of the channel.  But in recent years, we are seeing whole, apparently healthy, tree-covered banks being torn up and lost to erosion in floods.  Having been on these rivers (and being an observant and curious river rat) for going on 65 years, this is by far the worst I’ve ever seen the banks on my most familiar rivers.  I never used to see whole rows of trees being ripped out of the banks, nor so many fresh downed trees in the river that long stretches of good water are unfishable because of all the tangles of trees.  What is different now from 40 years ago?

First, we have to discuss the mechanisms of floods and flood damage a bit more.  We all know that floods cause the damage to banks, eroding them and thus widening the river.  But these rivers have experienced floods since the last ice age.  Floods do not ordinarily damage healthy banks; if they did, the rivers would have long ago become as they were back then, wide, braided gravel channels covering the whole valley bottom.  The reason this hasn’t yet happened is because the power of a flood, as impressive as it is, is diffuse; spread out over a whole bank from top to bottom.  If the bank is healthy, covered in vegetation, tied together with tangled tree roots, it can withstand the flood.  But give the flood a weak point to attack, and it will begin to eat away that point.  A piece of bare, vertical mud bank, devoid of roots, is enough if the mud is already wet and loose.  Once it begins to gnaw into that weak spot, it enlarges it, undermines the edges, and rips some of it away. 

But Ozark floods drop almost as quickly as they come up.  Ordinarily, the flood might not have time to excavate much of that bank.  The scar recovers, perhaps gets some vegetation growing on it.  It becomes healthy enough to withstand the next flood.  But only as long as that next flood doesn’t come too quickly.  And only if the wound gets the chance to heal itself.

Which brings us to the two reasons I believe floods in recent years have done so much damage. 

First, I’ve already noted that there have been more big floods in the last 55 years by far than in the previous 55 years.  But there is another component; there are simply more frequent floods some years, with only short periods of time between them.  The banks never get a chance to heal before the next flood strikes, nor does the alluvium have time to dry out.  One flood starts the damage, the next one rips out some trees, leaving big scars, and then another one comes along and rips even more of the bank away.

So it is the frequency of flooding that is different.  But there is another difference.  I cannot prove this myself, and as far as I know there have been no scientific studies confirming it.  But jet boat wakes are the other wild card in the mix.

Jet boats first began to show up on the larger Ozark streams in the 1970s, but did not really become popular until the 1980s.  By the late 1980s, some of us old timers (who weren’t nearly as old back then) began to notice more changes on rivers like the Current and middle Meramec.  The riffles seemed to be getting wider and shallower, with less well-defined channels.  Places with fast water and alluvial banks were beginning to see more bank erosion after floods even at that point.

Why?  Think about this.  All you have to do is visit the middle Meramec on a summer weekend to see a likely cause.  There will be jet boats going by you, one after another, a hundred or more wakes pounding the shorelines each day.  And these wakes will be causing any shoreline that is not covered in rocks to spew mud into the river, gradually extending a mudline until by mid-afternoon the whole river is much murkier than it was that morning.  All that mud is being chewed off the banks by the incessant wakes.  That is a lot of mud, and it is all coming from that one narrow zone of shoreline, just a few inches above and below the waterline.  It is an indication that the zone along the waterline is being damaged by the wakes; the mud is not appearing out of thin air.  It is being removed from the banks, and that is wearing small weak points in those banks.  In itself, it is not doing any obvious damage, but it is giving the floods those small zones to attack that wouldn’t have been there without the wakes.  And once the weak points are attacked by the flood, the same dominoes fall; the weak spots expand, a whole section of bank is weakened, and the damage spreads.

And as the banks erode, the river widens.  A wider channel flowing the same volume of water is a shallower channel; no excess gravel necessary.

And there is one more major factor in the pools of the Ozark streams filling in; the gravel in the channels is moving more than it should.  A natural gravel bar is somewhat stable; huge floods will move it, but smaller floods may not.  Small trees like willows, maples, and sycamores, water willow weedbeds, and other vegetation grow on gravel bars and help stabilize them, but even a bare gravel bar is usually somewhat stable.  The gravel is weakly cemented by silt on the surface in what the experts call “armoring”.  Drive a vehicle out onto a gravel bar, and as long as you go slowly and don’t spin the wheels, the tires will usually stay on top of the gravel.  But if you break through that surface armor, the gravel beneath is far looser and less stable, and you immediately sink to the axles.

So anything that disturbs that armoring is going to make the gravel move more extensively in floods.  A major culprit, especially on smaller streams, is ATV use. It has been illegal to drive ATVs into, across, and up and down stream beds for a couple decades now, but the law is widely ignored.  Take a look on Google Earth if you don’t believe this.  You’ll see ATV tracks covering gravel bar after gravel bar on just about any stream with big gravel bars.  On some nearly dry tributaries, you’ll see tracks going for miles down the stream.  Those tracks are an indication the gravel bars and stream bed are not in any semblance of stability.  Floods will move that gravel.  Even a small flood will pick it up and deposit it at the next spot the current slows—which will usually be the next deep pool.  A huge flood might pick it up and deposit it all the way out in the bottom fields, but numerous smaller floods just move it downstream in the channel.

That’s where we are now.  We are seeing the channels filled in with new gravel, ice age gravel being excavated by bank erosion, “legacy” gravel already in the system moving downstream and filling in pools, and it’s all exacerbated by bank erosion widening the channels.  The gravel is mostly natural, but it has become more harmful because of various human activities.

How to Be a Real Riverman

I wrote this piece for the River Hills Traveler back in the 1983.  It was a different time then in many ways.  Jet boats were not popular everywhere, kayaks and rafts were almost unheard of as rental craft, and aluminum canoes were the usual way to get down the rivers.  Not that they weren't crowded; weekends saw the aluminum hatch on the more popular rivers.  But it was not long removed from the days of the old wooden johnboats and guided float trips.  I have edited it and changed a few things from the original article, but it was a fun one to write.  I hope you enjoy it!

How to Be a Real Riverman

Lately I've been hearing a lot about this new book called, "Real Men Don't Eat Quiche".  I haven't read it yet, but I already know that it has some questionable propositions.  Even though I don't know how to pronounce "quiche", I have eaten it and liked it. I assume the book is about how to be a real man.  But it did give me an idea; I think what this corner of the world needs is a book--or maybe just an article because it isn't THAT important--on how to be a real riverman.

There was a time when about the only people that ventured onto our Ozark streams were veteran rivermen; the native hunters and fishermen and giggers and log rafters; the guides with their younger apprentices running the commissary boat and their rich clients from the city.  Nowadays, the streams are full of novices.  Inexperienced paddlers and families out for  a weekend of casual fun mix with drunken 20-somethings and party animals.  Those of us who have spent every hour we could on the river all our lives--and who would live on it if we could--tend to look with contempt upon the weekend splash and giggle and chug boat bangers.  They may not care much for us, either, but surely it's just jealousy.  They must think that people who look as grubby and smell as bad as we usually do after a week on the river shouldn't be enjoying ourselves that much.  Surely, deep down, they aspire to be true rivermen.

It isn't easy to be a real riverman.  It helps to be born within a mile or so of a good float stream so that you can get an early start on spending every hour you can, including many hours you shouldn't, on the river.  It takes that kind of time and dedication.  Perhaps you may not have that kind of time or opportunity; and incredible as it may seem, perhaps you might not even want to after seeing us after the aforementioned 5 days on the river.  But if you don't want us true rivermen to snicker smugly when we see you wearing swimming trunks and so much sunscreen that you look like you fell into the lard rendering kettle, you might want to learn a bit about how to speak and act well enough to pass for one of us from across the river.  And before you jump all over me, yes, women can qualify, but "riverwoman" or "rivergirl" just doesn't have the right ring to it, and don't expect me to call you a "riverperson".

If, like most of us these days, you use a canoe, you're at a disadvantage when it comes to being convincing as a riverman.  The old timers never used anything but wooden johnboats.  But since real johnboats are scarcer these days than mud flats on Current River, genuine rivermen have been forced into using other craft.  Many opt for aluminum jonboats.  (Note the different spelling--johnboats with an "h" describe only the old clunky, heavy as your mother-in-law's milk gravy but surprisingly graceful when drifting down the river wooden classics.  The more sophisticated but more effete "jon" without the "h" serves when talking about the newer aluminum imitations.)  And never mind what to call the lumbering behemoths with 100 horsepower jet engines that have started showing up.  A motorhead who runs up and down the river 20 times a day like a brain-dead crawdad is so far from a riverman there is no hope.

Some rivermen have switched to canoes.  Not rental canoes with their shiny aluminum skins and bows painted in distinctive colors so they can be sorted out by the dozen outfitters all picking up clients at the same take out on Saturday afternoon; a real riverman's canoe will usually be spray painted the ugliest set of camouflage colors he could find, with about half the paint chipped off.

Now if you have trouble keeping your canoe upright, you're just not going to pass as a real riverman...unless you have the presence of mind to clamber out of the water after a spectacular flip with a disgusted expression on your face, muttering that you "ain't got the hang o' handlin' them dang kay-noos yet.  Wisht I still had my ol' johnboat."

As to your other gear, in recent years rivermen have begun to find out about stuff like lightweight paddles and quality camping gear, especially the stuff developed by those idiot backpackers whose warped minds think it makes sense to carry your camp on your back instead of in your boat.  Real rivermen don't have to suffer; good gear makes anything more fun.  But if you want to look the part, you should have at least one rough-looking handmade ash paddle weighing about 30 pounds with you at all times.  You can keep it in the bottom of the canoe and only drag it out when you've set up camp with your buddies and want to show it off around the campfire.  For real authenticity, you should probably keep a piece of moth-eaten threadbare canvas tarp and a blackened coffee pot that looks like World War II surplus.

True rivermen are never found in a watercraft on any river without their fishing tackle.  That is one of the main things that distinguishes them from the the "tourist kay-nooers".  They might be fishing for goggle-eye (which you should never call "rock bass" no matter what the book says, let alone one of those other goggle-eye names like shadow bass and Ozark bass).  They might even be fishing for catfish if they are hungry enough.  But mostly they'll be fishing for bass, which in reality means smallmouth; largemouth and spotted bass barely deserve the name so they should be called "linesides".  A few real rivermen use a fly rod, but they are kinda like your rich cousin that everybody likes until they have to spend more than two days with him.  Some fish with spinning tackle, they are contaminated with the city angler syndrome.  Most use baitcasting tackle and "plugs", a catch-all name for any artificial lure other than flies.  Short, nondescript rods and beat up reels are the norm.  Push-button spincast reels are strictly forbidden; if you use one, it's a "Zebco no-brainer" no matter which brand it is, and you are only using it because you don't have the brains to master a baitcaster.

Real rivermen can always catch fish, except for the times when they forget themselves and brag that they can always catch enough fish to feed themselves.  An example of this was the recent float my girlfriend Mary and I made with my brother Don and his girlfriend Connie, and I assured them that I'd never made this float without catching some good bass.  Naturally, on this trip none of us caught anything over 10 inches.  Of course, the water was too clear.  That's another mark of a good riverman; the ability to make plausible excuses for bad days.  Another of the best excuses, especially if it's a weekend as it was on the Meramec trip, concerns "them dang boat-bangin' pleasure kay-nooers scarin' all the fish".

It's always possible to catch green sunfish and longear sunfish on Ozark streams, but whenever a real riverman catches them he will invariably cuss those "black perch" and "sun perch"--though he may keep them if he's been bragging about his ability to catch bass (see the above). They must always be looked upon with disdain even if they save an otherwise fishless day.

Real rivermen don't spend the winter watching TV.  They are out on the river, turning their feet to fudgecicles trying to catch a jack salmon.  Some people say that a jack salmon (jack for short) is a walleye.  That may be what you call those little fellers up in Minnesota or some other frozen northern place, but around here they are jack salmon, and you aren't a real riverman until you catch one over ten pounds.  You can fish for them with plugs, but if you use minnows you're a walleye fisherman, probably from Wisconsin or even Kansas.  Jack fishermen use "minners", and jack minners are big enough to furnish you a "minner dinner" if you've bragged that you can always catch jack (see above again).

Genuine rivermen never hesitate to run the worst rapids they encounter, though you don't call them rapids, you call them shoals or chutes or "god-awful waterfalls".  However, having the skills to match your confidence isn't mandatory, so when you get into trouble in a hairy place, you bail out before you hit it and try to swim and wade dragging the canoe to get it away from the hazard.  And you're always ready with a plausible excuse again, like "danged river's changed some since the last time I ran this spot".  Another excuse, which I used to good advantage the only time I flipped a canoe, is "this boat handles different with a full load".  A riverman's skill with a paddle is one of his prides in life.  Any riverman can paddle from the same side all day long without switching, even though at times it would have been a good idea to switch.  And a real riverman can paddle all day with one hand, because the other usually holds his fishing rod.

As you may have surmised if you've read this far, a real riverman uses the proper vocabulary.  We've already touched upon the proper names of some fish, though we haven't mentioned "yaller suckers" (redhorse) or "hog-mollies" (hogsuckers).  However, there are plenty more words and phrases you need to learn.  No matter what kind of watercraft you use, you go on "float trips", not canoe trips or paddling trips.  The start of a float is the "put-in".  The finish spot is the "take-out".  And try to learn the real names of accesses.  One of the most used take-outs on upper Black River used to have a giant round yellow sign, with two black dot eyes and a curving smile line beneath them,q on the bank to show the novices where to take out, but under no circumstances should you call it the "smiley face place" like the non-rivermen do; it's the Coil Bluff take-out (even though it's a bit upstream from Coil Bluff).

Hollers come down to the river, not ravines or swales or even hollows.  That sheer rock face is a bluff, not a cliff, and real rivermen know the names of bluffs even if they have to fake it.  We've touched upon what to call riffles and rapids, but if you ever call it a "ripple", you instantly forfeit your riverman card.  And if you call it a "scary place", there's no hope for you.  Slow, deep sections should never be called pools; they are holes or eddies.  A slough or backwater might be called a "slew", but just as acceptable is calling it a bay.  A narrs or narrers is sometimes a narrow place on the river but more likely a thin spine of rock with a stream on both sides.

Real rivermen know the names of every river feature.  If it's a hill, a mountain, a ridge, a creek, or a spring, it has a name.  A typical riverman's trip description might go like this:  

"Yup, I put in at Two Rivers.  Got into a mess of goggle-eye and little bass there around Coot Chute.  Caught a couple nice jack at the mouth of Goose Bay, an' a good bass in that hole where Blair Creek dumps in.  Seen a 10-point buck at Boomin' Shoals Holler, and a flock o' turkey came offa Butt-in Rock and flew over me.  Whole passel of pleasure kay-nooers around Blue Spring.  Hung a big jack in the Ant Hole and lost her.  Took out at Paint Rock Bluff, and that road in is a real bear after the last gulley washer."

More important than the rest, a real riverman truly cares about the rivers.  He is vitally interested in maintaining fish and wildlife populations.  He's not a game violator and he reports those who are when he sees them.  Any potential danger to a stream is a personal threat.  Dams are crimes against nature.  Real estate developments should be wiped out by massive floods.  Polluters should be hanged and litterers flogged.  And people who don't care about wild rivers and use them only as amusement parks and bars and aquatic racetracks are considerably lower than tapeworms.  When you feel that way, you are well on your way to becoming a real riverman.

Latest Update on Using USGS River Gauges

 The U.S. Geological Survey real time river gauges have been invaluable to those of us who paddle, row, motor, and fish the streams of the United States.  But they have been going through a lot of changes in the last few years, a few of them good, most of them (in my opinion) not so good.  I've written here before on how to get the most out of them, and in many ways the changes have made getting the most out of them more difficult.  

I had worked out a perfect system for efficient gathering of the information I most needed on the old website.  I had bookmarked, both on my phone and on my laptop and desktop, a page that had a table of all available gauges for the states I was interested in, grouped by river system.  The table listed the gauges, the links to click on for each gauge, and most importantly, the present discharge in cubic feet per second AND the median discharge for the day.  The median is a good approximation of normal.  So I could immediately see what any stream I might be interested in was flowing, and how close it was to normal flow.  Very often that's all I needed to know; if it was near normal and there hadn't been any significant rain in the last few days, I knew the river was floatable or fishable.  And if there had been rain or if the gauge showed levels well above normal, then I could click on the link to that gauge and see exactly what was happening.

So imagine my dismay when one day in 2025 I clicked on that statewide streamflow table page in my favorites, and the page was GONE.  The easiest, simplest, most useful single page in the whole river gauges website, and they dumped it.  There was a place to register comments, and I immediately clicked on it and complained.  I got a nice response back saying basically nothing, and not acknowledging how stupid it was to get rid of that page.  

Instead, there was a map, showing the counties of the state, with little tiny dots to click on for each gauge.  You have to be terrific at geography to know the exact location within a county, or even which county, a given gauge is located.  It was basically guessing, clicking, and seeing if the right gauge came up.  All that info on present flow and median flow was just gone.  One thing the response to my comment did say was that I could put gauges into a "favorites" page.  Otherwise, my only choices were to click dots on that map, or scroll down through the list (which in most states is 200 or more gauges) to find the gauge I wanted.

So, I started exploring that "favorites" idea.  Well, it turned out to be SLIGHTLY more useful.  You could eliminate all the gauges you're NOT interested in within the state.  You could make your list of favorites be grouped by river system and not county, which helped considerably to find them.  You could even click on one button once you get your favorites page up, and have it show the present levels in feet and discharge in cfs for every gauge in your list.  But NO option for it to show the median flow.  For that, you had to go to the individual gauge page and click a few more times.

Since I live in both Missouri and Montana part of the year, and also do some floating and fishing in Arkansas, I needed to set up favorites pages for all three.  Most people probably wouldn't need to do so; their home state is probably all they are usually wanting to bookmark.  And they might not be interested enough in streams on the other side of their state to bother putting them in their favorites list.  For them, the favorites list would be fairly simple to use.  For me...I started out with 85 gauges in my favorites list for Missouri alone.  

So I made a revision on how to use these river gauges, explaining the favorites method.  Meanwhile, the USGS kept tinkering with the gauge pages, and by now some things have changed, and I've made some more decisions on the best ways for me to use the gauge pages, and have discarded the whole "favorites" feature again.  In this article, I had gone through how to set up and use the favorites feature, but then I was going to get rid of all those directions and just go through the simplest ways I've found to use the gauge website. 

However, I realize that my situation is different from what many need.  I'm interested in, and often checking, gauges all over the Ozarks and Montana, and occasionally in other states.  But many people almost never use gauges for more than a few streams close to home that they paddle or fish frequently.  So I went back through the favorites system, which has changed slightly since this article was originally written.  I will start out by showing the steps to take to use the gauges my way, and then show how to set up a favorites system.

Here is how I use the gauges.  Note: I took these images off my smart phone.  The pages may look slightly different on a laptop or desktop computer. 

First, locate the beginning page for the state you want.  For Missouri, it will be "waterdata.usgs.gov/state/Missouri"  

You can start out by doing a Google search for "usgs river gauges (your state)".  When I did this for Missouri, the top search result was "USGS Current Water Data for Missouri".  When you click on it, or enter the link above, you will get this page:

About the only thing useful here is that you can change to a different state easily.  But scroll down, and this map will show up:

This shows the location of all the gauges in the state.  It shows the rivers those gauges are on, but it doesn't name the rivers.  So you must have some geographical knowledge to recognize the river where you're wanting to find a gauge.  This may be the hardest part for many people.  It certainly could have been done differently.  But THIS IS THE PAGE I BOOKMARK ON ALL MY DEVICES, BECAUSE FROM HERE I CAN GET TO THE INDIVIDUAL GAUGE PAGES I WANT. I haven't even bothered to bookmark individual gauge pages, because it's simple enough to get to them from this page.

(Note that the gauge circles are different colors.  The colors denote whether the gauge is "0-5, extremely below"--dark brown, 5-10, much below"--medium brown, "10-25, below"--light tan, "25-75, normal"--light green, "75-90, above"--light blue, 90-95, much above"--medium blue, and "95-100, Extremely above"--dark blue.  The figures denote the percentile of all the flows of record on the date--for instance, a 5 percentile flow means the flows were only lower than that on 5% of the days of record.  You might also see those red exclamation points on some of the circles, which means that the river is flooding at that gauge.  If you scrolled down a bit on this screen, you'd see an explanation of all this.)

You can zoom in on the map by spreading with two fingers on your smart phone to make it easier to see the gauges and click on the gauge you want.  Note that there is an intermittent glitch where when you zoom in, the little circles for the gauges get bigger.  If this happens you can't do anything else, you have to reopen the page.  But if all works right, zooming in on the map should look like this:

Here I've zoomed in on the region that has the Jacks Fork and Current River above the Jacks Fork.  You can see the three gauges on the Jacks Fork.  Say I'm interested in the uppermost gauge.  I click on its little circle.  Here is what happens:

The little circle gets highlighted in orange, the gauge is named below it, and information about the gauge shows up below the name.  This MIGHT be all the information you need.  You can see that this gauge's discharge is 82.7 cubic feet per second, and the little green box saying "normal" means that according to the USGS figures, the river is at a normal level at this gauge.  

If we use the "favorites" system, reaching this point is different, so I'll go through it now.  You can decide whether or not you want to use "favorites".  As you will see, it takes some setting up, and is time consuming if you want to add a lot of gauges to your favorites.  But it might be a better way to go if you only want to monitor a few gauges.

Starting with that opening page showing the map of all the gauges, you scroll down to this screen:

You can see three buttons for "Group monitoring locations by".  If you know the counties the gauges that interest you are in, you can leave the button selected for "County".  If you know the gauges by which river they are on, you'll want to select "HUC-8 basin".  I selected the second option.  Below this screen, as you continue to scroll down the page, you'll see information for every gauge, grouped by the major river.  Let's say I want to add only the fishable streams of the Meramec and Gasconade river systems to my favorites list.  I will scroll down until I reach dark gray headings for the larger streams in those two systems.  Here is the screen for the Meramec River and tributaries heading:

I'm not interested in the two small, minor tributaries shown on this screen, so I keep scrolling down.  Here I've come upon the Huzzah Creek gauge, which I want to add to my favorites.  Note that by clicking on "View 7 day graph", I can reach the actual page for this gauge.  But right now I'm only going to click on "Select for My favorites":

I keep scrolling down, selecting the gauges that interest me of the Meramec and minor tributaries.  Then I come to the heading for the Bourbeuse River, which I know is one of the two major tributaries of the Meramec.  I click on the two gauges on it.  And then the gauges on Big River, the other major tributary, come next.  I continue doing this, finding the Upper Gasconade, Big Piney, and Lower Gasconade.  I end up with 21 gauges selected for my favorites, which I can see by scrolling back up to near the top of the page, where I was before.   Now that screen looks like this--it shows a checkmark and "21 Locations selected".  Right below that is "Show My Favorites options", as well as "View your My Favorites page":

You can click on the options to check the locations you've selected and remove any you don't want.  But if you're sure you've selected the ones you want, you just click on the "View your My Favorites page".  It will look like this:

To insure you get data, I would click on both the button for "Show only data types with data in the last 120 days" and "Show data type period of record details".  Now you can bookmark this page in all your devices.  As you scroll down it, you will come to the first of the gauges you've selected:

 Just above it is a button to click for "Show all latest values".  Note that at this point, the gauges are listed but no other information on the gauges is shown.  But if you click on that "Show all latest values" button, you will see that when you scroll through the gauges below, they will give you the present gauge height in feet and discharge in cubic feet per second: 

If you click on the "View all recent data as separate graphs", you will get graphs for height in feet, discharge in cfs, and any other information being graphed by the gauge.  But you still won't get to the actual gauge page that has ALL the info you want.  So instead you click on the blue "View Monitoring location page" at the top of the gauge heading to get to the actual gauge page.

So to recap, I've given you two ways to set up your river gauge bookmark and select the gauge pages you want to view.  In each one, once you click on the "view monitoring location page" to get all the information you will need, it will take you to this page:

You may want to know the exact location of this gauge if you're not sure you have the right one, so you can scroll down the page to reach a map showing its location:

You can use two fingers to move the map around or zoom it in or out, and thus further locate the gauge or find other gauges.  But now you are ready to get into the meat of the gauge page.  Scroll down from the opening screen to reach the graph showing what the river has done in the last seven days:

This shows that the upper Jacks Fork saw a very slight rise a few days ago, but then continued to drop until yesterday, when it got a slight jump before again dropping.  Note, on the left side of the graph, the increments being measured.  We are talking about fractions of an inch of rise, not feet, so you need to pay attention to the increments being measured.  A real rise will look like the one for upper Big River during this same time period:

Now look at the increments on the left.  The river went from well below 4 feet to well above 10 feet.  To find out exactly how much it rose, there is a slider bar just below the graph.  I have slid the vertical line to the peak of the rise, and at the top of the graph it shows that the river was at 11.42 feet on July 10th at 12;30 PM.  I can now slide the line to what the level was before the rise began:

It shows that the river was at 2.74 feet at that time.  So doing the math, the rise was 8.68 feet.  Then the river began to drop, but had another smaller rise before dropping toward where it is at this time.

You can also see that the river was stable before the rise, and being stable for days like that means it was at normal or low conditions until the rise.

But back to our upper Jacks Fork gauge.  The height in feet is useful for gauging how much a river has risen, but it does nothing to tell you if it is at a normal level, or if there is enough water to float in lower water conditions.  So you don't want the graph for level in feet, you want a graph for the discharge in cubic feet per second.  And for that you have to scroll down until you reach this point:

There is a "graph it" button for "Discharge, cubic feet per second".  Click on it and the screen changes to this:

It shows that the cfs is now graphed.  It also gives you a button to click for "Median day of year statistics--indication of normal levels"!  This is important stuff, so click on it. But before you do, you MIGHT see that button at the bottom for "Temperature, water, degrees Celcius".  Only a small percentage of gauges have temperature readings, but they can be extremely useful for anglers in the colder weather periods.  

Once you click on the median day of year statistics, scroll back up to the graph, and it will now look like this:

Now we are getting somewhere.  The blue line shows what the river has done for the last week, in cubic feet per second.  The gray horizontal lines, one for each day, shows the median flow for that day.  So you can immediately see that the river has been maintaining a flow somewhat above the median, which is, as it said, an indication of normal levels FOR THIS TIME OF YEAR.  Normal levels in the spring are much higher than normals for mid-summer to autumn.  

Below the graph is one of the biggest pieces of information to click on, "Show today's statistics".  Click on the downward pointing arrow, and you get this:

It shows the exact median flow for today (in this case, 45.45 cfs--instead of abbreviating to cfs, they abbreviate to ft^3/s, but it's the same thing).  Please understand that this is the figure at which 50% of the flows ever recorded on this date were higher, and 50% lower.  Remember, it's the best approximation of normal flow for the date.  Then there is the 25th (percentile) at 39.2 cfs (the flow which was exceeded 75% of the time--in other words a very low flow for the date) and the 75th (percentile) flow (the flow only exceeded 25% of the time).  Note that the USGS considers any flow between the 25th and 75th percentile to be in the normal range, which is what the little green "normal" box I pointed out before signifies.  It also shows the "low"--the lowest flow ever recorded on this date--at 22.6 cfs, and the "high", highest flow ever recorded on this date--at 2980 cfs.  Both are interesting but not really useful for our purposes.  It also shows the "mean", at 250.012 cfs.  The mean is the average of all flows recorded on the date, and you might think it would be more useful than it is.  In fact, at least one of the apps thinks it's useful and shows it.  But it is NOT a good indication of normal flows, because it is always skewed upwards by the highest flows being so much higher than normal than the lowest flow are lower than normal.  So in reality it is completely useless and you can ignore it!

When you've gotten to this page, you now have all the information you really need to know almost exactly what the river conditions are.  You've found out whether or not it has had a rise in the last 7 days.  You know how high the rise was if it happened.  You know what it is doing now; steady, dropping, or rising.  You know how many cubic feet per second it is flowing.  You know what the normal flow is for this time of year in cubic feet per second, so you know whether the river is near normal, higher than normal, or lower than normal.  And now all you have to do is remember a few numbers and what they mean.

First, if there has been significant rain, the question will probably be, "is the river too high to float?"  Well, if there has been a rise, how high was it and how long ago was it?  And here are the general guidelines:

If the river was fairly stable before the rise, and the rise was 1 foot or less, you can figure that even at the top of the rise, the river was still close to normal and remained clear, so it should have been just as easily floated as before the rise.  If the rise was 1 to 2 feet, that's enough water that the current becomes much more powerful.  It should still be floatable if you have some paddling experience, and probably not totally muddy, so it should still be fishable.  If the rise is 2-3 feet, it might still be floatable, but only for paddlers experienced in fast, heavy water.  The consequences of mistakes can become severe and even life-threatening, and the inexperienced show avoid floating it.  It will probably be muddy, too, so fishermen will want to avoid it.  If the rise is over 3 feet, simply stay off it!

After a rise on a smaller, clearer stream, it can drop back to near normal in just 2-4 days.  On a larger stream like the middle Current or Meramec, it can take 4-7 days to get back to normal.  Once it drops to within a foot or two of what it was flowing before the rise, it should be in good enough shape to float.

In mid to late summer through fall, the question you want answered is more likely to be "is it too low to float?"  And for that, you only have to remember one very easy to remember number: 100 cubic feet per second.  On any stream in the Ozarks that CAN get too low to float, 100 cfs is the absolute minimum flow for floating without a lot of scraping bottom and possibly dragging your boat through some riffles.  If it's below 100 cfs, expect to have to work at it a bit.  If it's below 75 cfs, you'll do a lot more work.  Under 50 cfs and you'll be walking most riffles.  On the other hand, 150 cfs is getting into the range where you'll be able to float every riffle unless you're poor at reading the water, and 200 cfs is entering the optimal range, where floating becomes easy and you should never scrape bottom.  But 100 cfs is the one number you really need to remember.  

There are other things you can do with the gauges.  You can call up what the flows were at a given point in the past.  Say you floated a stretch of river years before, on a date that you can remember, and you want to know how it looks now compared to what you remember it being back then.  There is a feature on the gauge page where you can go back and look at any time period when the gauge was recording.  I was planning a trip on the John Day River in Oregon a few years ago, on a stretch that I'd been on only twice before--the first time in the 1980s, the second time in the early 1990s.  I couldn't remember the date, except that I DID remember that one of my buddies on the trip had his birthday during it.  So I called him up and asked him what date was his birthday, and thus knew that the trip was around that date in 1992.  The John Day is a somewhat different type of river than Ozark streams, and I knew it could get too low to float in late summer, but I didn't know what kind of flow was the minimum for easy floating on it.  But I could remember how easy it was to float on that 1992 trip, so I called up that week in 1992 on the gauge page for the lower John Day, and saw that it had been flowing around 250-275 cfs then.  So I had a baseline for knowing whether there was going to be enough water for the trip I was planning.  As it turned out, the flow the gauge showed just before we left on the trip was 350 cfs, and the John Day almost never gets heavy rain in the summer; it's a high desert canyon river in central Oregon.  So I knew we were going to have great water conditions for floating it.

I've always said that the USGS river gauges are better than any of the apps you can get, since the apps all use the USGS gauges for their info, and do not offer as much info as the gauge pages themselves do.  But given the number of steps it now takes to access all the information I want in the USGS gauges, the question arises whether the apps are now better or easier options.

So I got several free apps onto my phone, and the answer to that, for me, is still no.  RiverApp is probably the best of them, but the closest it comes to showing the VERY important information on median (normal) flows is a line on the graph showing the yearly average flow at that gauge.  That is NOT good information.  And if you pay for the premium, you get MONTHLY average flows.  Average flows are NOT median flows.  Average flows are skewed upwards by big floods in the past, that are figured into the average.  The average flow will always be significantly higher than the median, which is the flow at which 50% of recorded flows for that day are higher, 50% lower.  It's a far better approximation of normal flow for the date.

Let me give an example.  The upper Jacks Fork in Missouri is a premier float stream that unfortunately is normally too low to float by early June.  A year ago in mid-May when I originally wrote this, the USGS gauge showed the median to be around 220 cfs.  But the RiverApp showed the yearly average to be about 270 cfs.  So, for this particular time of year, there isn't a whole lot of difference between the yearly average per RiverApp, and the median per the USGS.  But...by August, the median flow of the upper Jacks Fork will be around 50 cfs.  And RiverApp will still be showing that yearly average of 270 cfs! 

There are a couple other sites you can go to for river gauge information.  The NOAA river gauge pages have a prediction service that shows what the stream is predicted to do in the next week based upon what it's doing now and predicted rainfall.  It is also easier to see the flood levels. But it leaves out a lot of the information, such as the median flow, that tell you what the river conditions really are.  I might go to it if I really want to get the best idea of what the river might do in the next few days, but otherwise I don't see any advantages to it compared to the USGS pages.

 There is one other bit of often useful information you could still get from the gauge, but I don't know how much longer it will be available. I've been unable to find it on the new pages themselves.  If you scroll back to the top of our gauge page we've been discussing, you'll find a link to "Legacy real time page".  Clicking it will take you back to the format of the old pages after a blurb saying that the page is going to be discontinued at some point.  Scroll down a bit and you'll find this to click on:

See that "Current stage-discharge rating"?  Click on it and it will give you a table that looks like this:

This takes a bit of explanation.  The gauge mechanism measures ONLY height in feet.  That is the raw measurement.  To convert height in feet into discharge in cubic feet per second, actual people have gone to the gauge site at different water levels, and physically measured the flow in cubic feet per second, and they periodically go back and remeasure it.  Thus they come up with a table that matches different heights in feet to the flow in cubic feet per second.  Those three columns on this page show that table.  The column on the left is a given height in feet.  The column on the right is its corresponding discharge in cfs.  The middle column doesn't matter for our purposes.  So if somebody tells you that a month ago the height in feet on the gauge of the river they fished was 2.3 feet, but they didn't check the discharge in cfs, you can go to this table and see what the river is flowing in cfs at a height of 2.3 feet.

In conclusion, I hope this helps you to understand the new gauge format, and how to find the most useful features.  There is a wealth of information in these gauges that most people don't know how to find or use.  They could be made easier and more user friendly, but once you learn to use them, they are better than any of the apps.