Thursday, September 3, 2015

The day the river died...


The National Weather Service report for April 16th, 1998:

"persistent heavy rainfall caused county creeks and streams to flood across roads.  A section of State Route 350 was washed out by the high water.  One hundred fifty people were evacuated from the banks of Turtle Creek while a total of 210 were evacuated across the county.  Seventy homes received minor damage and 5 had major damage.
The Little Miami River rose out of its banks from Kings Mills to Milford.  At Kings Mills, the river crested at 24.0 feet around 3pm EST on the 16th.  Flood stage is 17.0 feet.  Some flooding occurred in South Lebanon and Morrow  in Warren county.  A police car was submerged by the rising flood water.  At Milford, the river crested at 21.3 feet around noon on the 16th.  Flood stage is 17.0 feet."

  If I remember right my dad's rain gauge showed it rained 4.5 inches in a couple hours in South Lebanon, up around Morrow there was even more, I remember people having over 9" in theirs. Between Morrow and South Lebanon is the little natural area of Hall's Creek. Here your right in the heart of the twenty mile long gorge cut by the Little Miami during the melting of the last glaciers. Halls creek falls steeply down the steep hillsides before joining the river. always pretty and full of small cascades, Halls Creek became a different place overnight. small head high waterfalls appeared in the creek and its little tributaries where none were before. And older ones were changed so much as to be unrecognizable.

As you pulled out of the parking area at Halls Creek and drove along river road even more changes were evident. Rocks were blown out of the tiny rivulets that were dry most of time. My father was building a small koi pond beside his house back then. He drove his old van along river road and loaded it full of rocks that has washed down and were scattered all over the roads edge.  A bit further along a tiny stream that was mostly just a muddy spot in the back of someone's yard most of the year had rose up and pushed the house off it's foundation. Now there is just an overgrown flat spot beside the road with a few block hidden in the grass to ever let you know it was ever there. Even right below Caesar Creek Dam was affected. A small dry creek running off the hill built a rock bar almost damming the stream where there was nothing the day before. Thirty plus years later as you walk up the sidewalk towards the dam you can see the tons of rock in that bar that was dumped overnight.

And so it was all along the gorge section of the river. It had been thirty years since the river had gotten that high. But it wasn't the actual level of the flood that had changed things so much. Instead it was that was all concentrated in one spot. All that floodwater poured off the steep hillsides dumping ton after ton of rock into the river.

After things had returned to some semblance on normalcy I made the hike down to my favorite fishing spot, the mouth of what I'll call Stream X. Well Stream X wasn't there anymore! The mouth of the creek had moved forty yards upstream. Its former mouth was a huge rock and gravel bar much of which is still there today. It felt like an old friend had passed away. Year after year, flood after flood, spring after spring, I've watched as the river goes about the work of carrying all the rock away. One year especially high water took the end off the bar depositing a line of rock downstream in the pool below. The water pouring around the bar and over these rocks in a chute of fast water has created just about the best smallmouth spot I know. Some years the bar regains a bit of ground but mostly loses in a slow tug of war with the river.  I now think of that day long ago as a rebirth instead of a death.

Watching how the river changes, both overnight and over decades, has made me realize what a dynamic, living thing a river actually is. I learned and began to appreciate terms like laminar flow and point bar and lateral sort. I found that not only knowing a bit about how a stream works will help your fishing it also will add enjoyment to that fishing.

For you see my experience with my little river is hardly unique. It's an average river in an average part of the country. In fact what makes it so interesting is what it shares with every other river on earth. For you see even though every river, creek, rivulet and dry creek bed is as different from every other as a fingerprint it is also the same. The same laws of physics apply to any flowing water, anywhere. If you know nothing of streams and want to learn the mighty Ohio or Mississippi rivers start with the creek in your back yard.

Every stream left to it's own devices and not encumbered by a hill, a giant rock formation, or for that matter a dam, will naturally form a series of serpentine curves as it flows. Thru these will run the channel of deepest water or thalweg. The thalweg is closest to the bank on the outside of each bend so the channel itself crosses over from one side to another as the stream turns. This is important to realize on a bigger stream as its our natural tendency to assume the middle of the river is the deepest point. Even in large navigable rivers that have been dammed the channel is still down there underneath for you to find. As the thalweg hits the back of each bend it digs out the bottom forming deeper bend pools. On the inside of each bend a rock or gravel bar is formed called a point bar. In between the pools roughly coinciding with where the channel crosses material from the pools is laid down forming a riffle. even in deeper rivers this building up of material goes on even if its not visible as a classic riffle. That in a nutshell is the basic principle. But nothing is ever that simple. The water doesn't flow even around the bend. It hits the back of the bend twisting and rolling over on itself creating a secondary current across the pool towards the point bar as well as flowing around the bend. And as we all know the outside of a wheel turns faster than the inside so the water gets progressively faster the further it is from the point bar. Throw in things like tree roots, substrate makeup, hills and land contours, etc, etc, etc, and you end up with millions of variations on the same theme.

But the key point here is that it is the same theme. If you walk that little creek in the backyard you can easily see all those forces at work. In a few hundred yards you might see three or four bend pools, tiny sand bars, little rock bars and eddies. And they are not there by chance but instead formed according to the laws of nature. That deep pool that's a foot deep on the tiny creek will still be there on the Ohio buried under all that water. If your wading your favorite small stream fishing an outside bend you know the channel will cross over and be on the other side up past that riffle in the next turn.

After a while you get to the point you can amuse yourself almost anywhere. You wander off and stare at the hydrology of a ditch during a soccer game. You picture how each section of the creek must look that you can see out the window during that long business meeting. Even the patterns in the sand of a baseball diamond after a rain were formed by the same forces. You can spend half an hour looking over a ditch line.

You also have to realize that a fishes world is a 3D one. Faster water might be over top slower water. A seam of fast water next to slow water is as obvious as a wall to a fish. An eddy behind a rock is a room where a bass can sit and wait as dinner is brought. When you first wade out into the river it all seems of one piece. But wait give it minute or ten till it starts to slow down in your head. Till you can see a flat piece of foam circling in the chaos below a riffle, till the current separates into individual streams. Till the whole river becomes individual pieces all fitting together like a jigsaw puzzle. That's how fish see their world. And though we can never even come close to their perception of it, the closer we come the better fishermen we become. And even more importantly the more enjoyable and richer our time on the river becomes.

And the list of things we can learn is endless. How different bottom substrates effect water acidity or turbidity. How the glaciers affected our streams. What the presence or lack of groundwater does to our streams. These may seem abstract things but they can have real and practical uses. My home river has abundant groundwater up in it's headwaters. Even to the point of reaching the surface in the form of swampy areas called fens. But many of it's tributaries are not so lucky and they can get low and warm in late summer. Too low and warm for good fishing. A good thing to know before you've driver half an hour to fish one.

When your not out walking the creek in the backyard another good place to start is the EPA's biological and water quality report index. In there you can find a report on any stream in Ohio. Much seems like scientific gobbledygook but if take to time to really look you can vast amounts of information about your stream. Things like watershed maps, vegetation maps of the basin, geological makeup. Also you can find out just how healthy your stream is, what the make up is of the fish community, what the outlook is for the future.

Just be warned, learning a small part of how the river does what it does can be a Pandora's box with far-reaching consequences. Like all thing associated with fishing it can be as simple or as complicated as we wish to make it. And never think that little creek in the back yard is too little to learn from. In many ways the smaller the creek the better it is to see how all the different forces at play work. A hundred yards of a really small creek might be comparable to a hundred miles of the Ohio. Don't take such a gift as having a whole world full of moving water to learn from for granted.

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