Many people with freshly dug lakes and ponds run into an issue of a muddy water body, yet this issue can be shared by both owners of new and old lakes and ponds alike. Whatever the age of the water body, muddy water bodies are almost always undesirable to lake and pond owners. For those managing water bodies for aesthetics, muddy water is an obvious negative and for those managing water bodies as fishing lakes, muddy water presents a multitude of problems. Chief among those problems is that with decreased sunlight penetration, photosynthetic organisms such as phytoplankton and plants cannot establish well. As phytoplankton represent the base of any lake food chain, this inhibits the growth potential and population carrying capacities of pretty much every other species in your lake. Therefore, this is a problem that almost everyone experiencing it will want to address. Yet, there can be multiple causes for muddy water, so before you decide to find a solution, let’s try to uncover the correct cause. Below are the four most probable causes of muddy water in Texas lakes and ponds.
The first possible cause of muddy water is a lack of vegetation on the banks of your lake or pond. Vegetation around a lake/pond is a critical component to ensuring erosion control. Essentially, the roots of plants grab onto dirt surrounding the lake and prevents it from being washed into the water column. Places with little to no surrounding vegetation often experience muddy water, especially after events such as rainstorms, which can exacerbate erosion and wash sediment into the water column. Lack of bank vegetation is especially common on newly dug ponds since often, owners overlook this key aspect of pond construction. Once species such as shrubs and forbs are planted along the shoreline of the pond, water clarity will usually improve. We recommend planting native species so that you know you are helping promote natural ecosystems that will be healthier and easier to maintain. There are many aquatic plant nurseries that can help with species selection if you are looking for guidance.
The second possible cause of muddy water is livestock. Many lake/pond owners that use their water body as an area for cows or other livestock to drink. Livestock can stir up the bottom sediment in a lake and increase shoreline erosion by their movement and foraging. We recommend limiting livestock access to your water body (i.e. using a fence) to mitigate this problem. Many pond owners see their pond clear up naturally after limiting livestock access.
The third possible cause of muddy water is undesirable fish species. Certain species such as Gizzard Shad and Bullhead Catfish feed in the benthic zone of ponds on things such as detritus and crustaceans. These species can rapidly overpopulate in many water bodies and cause muddy water due to their ability to stir up bottom sediments, resuspending them in the water column. Electrofishing surveys are a great way to tell if this is the muddy water culprit, or at least a contributing factor. When it has been determined that undesirable fish species are the cause of the pond’s muddy appearance, pond owners often must choose between intensive electrofish culling of unwanted species or a non-selective chemical piscicide application for removal.
The final main cause of muddy waters in Texas is colloidal clay, which means tiny clay particles that remain suspended in the water column and will not drop out without water chemistry alterations. Because of their high surface area to volume ratio and the electrical charge associated with them, these particles are attracted to water molecules and will sit in place until changes in water chemistry allow for them to settle. To deal with turbidity caused by colloidal clay, we recommend flocculants or coagulants such as alum (aluminum sulfate) and gypsum (calcium sulfate dihydrate).
To understand the source of your muddy water, we first recommend putting some of your lake/pond water into a bucket or jar and leaving it for a week. If after a week, your water is cleared up, you know that your problem is likely due to livestock, undesirable fish species or shoreline erosion. If your water remains muddy after a week sitting in a jar or bucket, we recommend doing the jar test with alum or gypsum. This involves combining small quantities of your chosen coagulant/flocculant with buckets containing equal amounts of pond water and extrapolating the amount of coagulant needed to clear the jar/bucket from the test. There are numerous online resources that will explain the jar test if you are interested in doing it yourself, or you can have us pick a sample up and perform the jar test for you. While muddy lakes are unsightly, the good news is that the problem is often easily identifiable and the solution often feasible.