Clearing Muddy Water

Checking visibility of a muddy lake to begin the process of clearing it.

By Bob Lusk

Early in my career, I had the pleasure of spending some time working on ponds on the internationally famous W.T. Waggoner Estate Ranch. That massive amount of land covers 550,000 acres in north Texas and sits in parts of six counties, near the town of Vernon. This iconic ranch recently has been in the news. It sold, much to the chagrin of the traditionalists…not to mention those deeply in touch with its heritage and history. Just for perspective, visualize a land mass about 30 miles wide and 50 miles long, in one contiguous piece of privately owned property. I bet there are 500 ponds and lakes on that parcel. Heck, they don’t even know how many ponds they have. Most were built for watering livestock, but beginning in the 1980’s, a few of them were designated for fishing. As I traveled around the ranch with the staff game warden (yes, they have private game wardens on staff), I became convinced there are places on that property where no human foot had ever trampled…ever. I also became convinced there are too many microclimates around that ranch to count. There are arid areas with rough, rock covered cedar breaks. There are fertile soils with enough rain to support good crops of wheat. Heck, one of those wheat fields covered 20,000 acres at that point in time. It took a full day for a tractor to plow around it one time.

But, the thing that stands out to me most of all, as a passionate pond guy, was how we could go into one pasture and see a pristine, beautiful, clear pond with a few trees around it and then go less than a quarter-mile and see a pond the same color as chocolate milk with an orange tint. There were some ponds on that property that I swear looked exactly like the barren red dirt that surrounded it. The only way you could tell it was a pond was because it was flat. Even more fascinating was the fact that some of these mud holes produced some giant bass. There were not many bass, but some of them learned to play the game in those muddy waters well enough to exceed thirteen pounds.

That ranch was my introduction into clearing muddy waters. We tried bales of hay that had been rained on and sometimes it helped. Often it didn’t. If not, we’d try aglime. Or, maybe some gypsum. After all, most of the clear waters on that ranch had measureable amounts of gypsum, which occurs naturally in some of the soils, especially on the western edges of that property.

Sure, we’d do the jar tests. We’d set up five or six one gallon glass pickle jars I’d grab from a football concession stand. Jar one was used as a control—just pond water. In Jars two-five, we’d add pond water and different concentrations of these various concoctions. It was fun, even if not totally helpful.

When it was all said and done, most of the time we used aluminum sulfate, alum, if you will. We’d launch a boat, have the alum in big plastic barrels sitting on a trailer backed up to the edge of the lake, and a water pump with hoses to draft pond water. On the intake side, we’d have a Venturi device we made by simply adding a smaller hose (like a one-inch hose) with a valve. The small hose was long enough to dip into a container of alum in the boat. We’d shove off with one guy driving the boat and another operating the pump. We’d mix and spray alum…and watch to see what happened to the water. At some point during that adventure, we began to see changes as little red clumps started forming in the water. It was like all those suspended clay particles became magnetic, attracting and sticking to each other. When that happened, it was our trigger to slow down. If we didn’t, we’d see a rapid pH shift in the water. A rapid pH shift would cause a fish kill. A fish kill would cause another loss…our job. It’s one of those “trickle down” economic effects. As we slowed down, the clumps would dissipate. It was fascinating to watch. We’d add a little more alum and wait. Clumps would form and then melt. Finally, when we reached the break point, the clumps would stick together, become heavy, and sink. A pond would go from chocolate milk to Caribbean blue in a matter of hours. Just as fascinating was how long a pond would stay clear after one of those treatments. We watched some of them go from muddy to clear overnight and right back to muddy the next day. We also saw some of them go clear and stay that way. It was unpredictable.

Today’s world is quite different. With our burgeoning industry, we now have resources we didn’t have back in the early 1980’s. Most pickle jars are now plastic and we have folks with microscopes in labs that can look at pond water and help us figure out why it’s so muddy… ‘er turbid. That’s the word today, turbid. There are people who have designed different products to assist with muddy, ‘er turbid, waters. Oh yes, there are still the methods of those days long ago, especially gypsum and alum, but now we can adjust the nutrients if turbidity is based around domination of a specific type of microorganism or a single cell plant or bacteria. There are also polymers available, which will specifically focus on removing certain suspended soils or solids and leave the nutrients alone.

Clearing Muddy Water 3

Just because water is turbid doesn’t mean fish can’t thrive.

So, nowadays, more effort is centered on diagnosing the issue and then prescribing a plan of action, rather than rolling the dice in a boat and shooting out a dose of alum. Not that those old methods won’t work, but it’s like comparing Grey Poupon mustard to French’s—it’s a refined taste. Remember one of the Laws of Nature: With every move we make, there’s a reaction in nature. Several of those Waggoner Ranch ponds we treated actually traded problems. I remember one in particular. It went from muddy to clear overnight and within a month was 90% covered in bushy pondweed. That clear water was shallow and all it needed was sunlight to grow bunches of plants all over the place.

More recently, we’ve done some work in central Texas, near the small burg of Hico, purportedly the final home of Billy the Kid. At least there’s a museum there about the notorious outlaw with all kinds of research proving he lived there.

Just outside Hico is John and Ellen McStay’s ranch. On that ranch resides a 14 acre lake teeming with nice bass and bluegills. The problem? The lake, which a few short years ago was a nice, healthy shade of green and you could see your feet in three feet of water, has gone turbid.

Mr. McStay became convinced the channel catfish in the lake kept it stirred up, so he and the ranch staff began harvesting catfish. Still muddy. Its color today resembles an olive-colored cupcake, sort of a deep-green batter-looking color. It doesn’t seem to be affecting the fishery, as that portion of the equation is thriving. But, it affects catching…or seems to. Team McStay can fish for hours with a minimum of luck compared to what fun they’ve had in the past and also when compared to a crystal clear lake on the ranch across the road. Launch an electrofishing boat in their lake and fish pop up all over the underwater creek channel and standing brush. But, toss out your favorite crankbait and nada, zilch, nothing.

Clearing Muddy Water 2

Collecting a sample to test with gypsum, alum or to simply see if the clay particles will settle on their own.

But, there is a difference worth thinking through. Several years ago, while in the throes of one of those 100 year droughts Texas seems to be having every couple of years, the lake level dropped dramatically. The McStay’s took advantage of the drought to deepen the upper end of the lake. They added several surface acres and deepened the shoreline of other parts of the lake. They added some well water and the rains came and re-filled the parched lake. A couple years later they noticed a difference. Starting about three or four years ago, the clear water changed. Visibility dropped. Over the last 12 months, they’ve faithfully kept visibility records. They’ve collected samples of water and sent them to different labs, hoping for some analysis that will lead to a magic bullet, maybe something as simple as that alum stuff. They’ve spoken with at least five water quality experts.

It’s become almost detective-esque, like some wet water novel, hopefully with a magical ending where everyone lives happily ever after and the fish jump into the boat, begging to be caught.

Water was collected, sent to a microbiologist and found to have almost 500,000 algae cells per milliliter. 77% of those cells were bluegreen algae, cyanobacteria, if you will. That explains the olive color tint to the water. But, there’s more. Suspended non-algae particulates were even more abundant and are at least 15 times more abundant than that green stuff. Interestingly, prior water samples suggest those suspended particulates are mostly diatoms which may have been dead for eons, literally.

This more scientific approach now leads the experts to think a multi-pronged attack may be necessary, because the “problem” has several layers. First, the cyanobacteria are most likely thriving because of an imbalance of nutrients. Recent research is proving that bluegreen algaes grow when the balance of nutrients leans too heavily on phosphorus. When the proportions of usable phosphorus exceed a 20:1 ratio compared to nitrogen, cyanobacteria tend to dominate. When those ratios are closer together, more of the healthy phytoplankton can thrive, outcompeting the useless and completely non-beneficial cyanobacteria.

But, that doesn’t speak to the suspended diatoms or any microscopic clay particles (which might be one and the same).

When we dipped some of the pond water and filled an empty Dr. Pepper bottle (spontaneously harvested from the floorboard of my truck), it wasn’t long before a little cloud of dust began to settle in the tiny nooks in the bottom of that plastic vessel. At home, we added a sprinkling of powdered alum and much of the remaining solids found its way to the bottom of the bottle. But, the water was still cloudy…with that green tint. Two different samples made their way to a lab and the results began to make sense.

From our initial samples and a year’s worth of data from multiple samples, different lab evaluations, plus several brains thinking about it, the problem(s) appear to be these:

  • Bluegreen algae due to a nutrient imbalance.
  • Physical stirring of the water, due in part to the fish, but moreso because of shallow, wind-swept water in the upper reaches of the lake.
  • Suspended solids, likely due in some part to the excavation of the shallow part of the lake back in the drought. Those soils are minute, most likely the source of diatom skeletons and clay particles.

The multi-pronged attack coming together is this:

  • Minimize stirring of the water. The best thoughts, so far, are to put some windbreaks into the shallowest part of the water. Square bales of hay make the most sense, as they are easy to get. It’s windy in that part of Texas, so limiting wave action is important.
  • Analyze the ratios of nitrogen, phosphorus, and potassium to see what they are and adjust the nutrients by adding the missing elements and changing the ratios.
  • Harvesting of those fish that tend to please themselves on the bottom of a lake. Targets? Channel catfish (which aren’t overly abundant any more) and gizzard shad (which we want to quantify).
  • Consider aluminum sulfate, after the other elements are in place.

Looking back on those days at the Waggoner Ranch, back around 1981-82, our approach was shotgun-like. It worked sometimes, and sometimes it didn’t. We always seemed to get immediate results, but had we raised the hood and looked more deeply, we might have taken a different path. But, who knew? We didn’t have same tools we have today. Now we can analyze things to death if we choose. The course of action will tell the tale. For this story, on this day, we can come to some conclusions before we ask the landowner to shell out some of his hard-earned dollars to try some solution that, in years past, might work, or it might not.