East Texas Ag News: Analyzing your pond’s water

Generic Pond
Generic Pond(WVLT)
Published: May. 31, 2024 at 10:43 AM CDT

LUFKIN, Texas (KTRE) - New landowners or landowners with a new pond often have questions on the quality of their water that they want to use in for fish production, irrigation, or to water livestock.

There can be a wide variance in water quality and what makes water suitable for fish production many have little to do with water that is good for irrigation and, furthermore, is different from what is acceptable for livestock or wildlife.

Without any laboratory testing, visually study your pond and look at the vegetation, look for small fish, and certainly look for frogs, crayfish (crawfish, craw-dads), insects, snails and such. Small fish and aquatic invertebrates are very sensitive to contaminants and imbalances in nutrients. The presence of all of these is a good indicator of a healthy ecosystem.

Obviously, the presence of young fish in your pond means that older fish are healthy and reproducing. Flip over a log or rock along the shore and look for insects, snails, and any kind of insect larvae. These small creatures survive on algae and even smaller invertebrates and are an excellent basis of the pond’s health. Additionally, these insects are often the food source for your larger fish and will aid in the health of your fish.

If raising fish is your primary objective, the pH and alkalinity should be your first constraint to study. Fish grow best when the water is at least 6.5 pH with an alkalinity of 20 ppm. Most Extension offices in Texas have kits to test for these two parameters. At my office in Angelina County, I offer these for free.

Irrigation water used on gardens, lawns, hay meadows, or orchards is concerned with the presence of salts, its pH, and nutrient levels. Some water sources may be naturally high in nutrient concentrations that, while one would think could be beneficial, may have too much of something that harms plants. The pH of water can also be extremely acidic or alkaline and affect the plants or certainly the soils in which the plants are growing.

A life-long county resident reached out to me with questions about the water in a pond on property she has recently purchased. She had some results from our wonderful, local river authority’s lab, the Angelina/Neches River Authority. She had the values of several nutrients, the pH, and alkalinity.

The results she received showed higher that normal levels of the following elements: magnesium, iron, manganese, and lead.

Now three of these elements are in fact plant nutrients and are necessary for plant health. The high levels reported suggests an influx of nutrients from accumulated plant material or runoff from nutrient sources upstream.

When studying what was upstream, only a pasture with livestock could be found. This was likely the source of those nutrients.

Of more concern was the presence of lead, even though it was far less than 1 part per million. The lab reports indicated a level higher than what was drinkable but this was a pond in the middle of forest and was not ever going to be used for drinking. The levels did fall below any concerns for fish or vegetation.

The source? An old pond such as this very well could have accumulated lead from old fishing weights or lead shot that was once used in hunting waterfowl. Even though lead shot was banned when hunting ducks, geese, and other waterfowl nationwide in 1991, lead can take decades, even up to 100′s of years to break down.

If you want to get technical and have a laboratory look at your pond water, you have options. Similar to water well testing, our local Angelina/Neches River Authority (ANRA) has some excellent tests. The Texas A&M Soil and Water Laboratory is another place to test your water for its chemical properties.

If you live in and around Angelina County, you can submit water samples to the Angelina Neches River Authority’s (ANRA) lab for analysis. For pond water, their “Basic Water Scan Package” looks at 12 parameters. These include alkalinity, chloride, fluoride, nitrates, nitrites, pH, sulfate, hardness, and more. Additionally, the Basic Water Scan will look for these metals: calcium, copper, iron, magnesium, manganese, zinc, and lead. Note that all these metals except lead are in fact nutrients necessary for plant growth and are in the multi-vitamin I take each morning!

If you are interested in more information on either of these tests, reach out ANRA at 936-632-7795 or email the lab at lab@anra.org. ANRA does plenty other testing that may be of interest. Their full website can be accessed at www.anra.org.

The “drinkability” water test that looks for the presence of E. coli in potable water would not be needed. Any pond water would be expected to be full of bacteria and other microbes unsuitable for drinking.

If you are looking to examine your pond’s water for potential irrigation, consider the Soil, Water, and Forage Testing Laboratory at the Texas A&M AgriLife Extension Service in College Station, Texas. You can reach the Laboratory at Texas A&M at (979) 321-5960 or email the lab at soiltesting@ag.tamu.edu. Their full website can be accessed at https//soiltesting.tamu.edu.