Pond management and maintenance can be a tricky process in a perfectly controlled environment. Add in fluctuating temperatures and rainfall, and it can be a nightmare. There are several key things to keep in mind that can help you keep your ponds healthy and a fun place to be this summer.
Depth is one of the most important and, most likely, the hardest to alter. At least a quarter of your pond should be 8-10 feet deep. This will help to keep your fish from being susceptible to winterkill by providing a temperature buffer and will help discourage aquatic plant growth.
Keeping the depth on your pond can be difficult as most of our eastern Kansas water bodies are extremely susceptible to sedimentation. It’s important to keep an eye on the water flowing into your pond and working to pull the sediment out of the water using grass buffers and other methods to prevent your pond from filling in.
And while the depth of your pond is important, the water needs to be continuously moving. Aeration plays a big role in that movement.
Keeping the water moving through either a current or a bubbler is beneficial for many reasons. Dissolved oxygen in the water is what fish need to be able to respire. It’s also what keeps the environment from becoming a purely anaerobic environment. When a pond becomes stagnant and anaerobic is when that funky smell comes into play. A stagnant and non-moving water body is also great habitat for mosquitoes. Keeping the water moving and healthy will prevent a mosquito population from getting out of control.
Dissolved oxygen also plays a role in the life cycle of nutrients in the pond, which brings us to our final consideration.
It’s no secret that nearly every water body in eastern Kansas will have fairly high levels of nitrogen and phosphorus. This comes from the runoff of our agricultural and landscaped lands. Fertilizers are used for high levels of vegetative growth, but not every bit of fertilizer is utilized by the plants. A fair amount of it is captured by runoff from our rain events and moved into our rivers, lakes, streams, and ponds.
This has a large impact on algal blooms and other plant life within our ponds. Algae and other water plants use photosynthesis for their energy production. They use sunlight, carbon dioxide, and water. Excess amounts of nitrogen and phosphorus in the water causes algae and other water plants to overproduce and throw off the natural balance. The algae and plants grow and reproduce like crazy. The now extraordinarily large amount of decaying algae and plant matter overwhelm the bacterial decomposers, cause a lack of oxygen in the water, and can lead to the death of fish and other animals dependent on oxygen in the water. This is what is known as eutrophication.
In our lakes used for recreation, eutrophication can most easily be seen by blue green algal blooms, or harmful algal blooms. Blue green algae is toxic to humans and other humans if ingested. It’s important to keep an eye on our ponds and lakes used for human recreation and consumption as algae can have a big impact on human health.
How do we control algal blooms and other vegetation from growing beyond our control? This can be tricky. It all comes down to the nitrogen and phosphorus in our waterways. Only apply the fertilizers that are needed to your agricultural land and landscaped areas. You can find out if you’re over applying by running a soil test. Call our office for details on that. We have a free soil testing program that can help you determine this. Make sure that any runoff that is coming into your pond is running through a grass buffer. This not only helps keep sediment from reaching your pond but can also help reduced the amount of nutrients reaching your pond, too.
Keeping a healthy pond isn’t an easy task but can be incredibly worth it. They can be the center of summer fun with the family and can provide many years of enjoyment if taken care of properly. Some parts of managing a pond can be expensive or difficult, and others can be a function of altering your fertilizer application on surrounding land.
For more on ponds, check out our website for more in-depth information at: https://www.johnson.k-state.edu/natural-resources/pond-management/index.html
The Kansas Department of Wildlife, Parks, & Tourism also has some great information on considerations for building a new pond that can be found here: https://ksoutdoors.com/Fishing/Special-Fishing-Programs-for-You/Pond-Management-Program/Producing-Fish-and-Wildlife-in-Kansas-Ponds/Pond-Construction-Consideration
And to know how the public lakes and reservoirs in the state of Kansas are doing, the Kansas Department of Health and Environment keeps an up-to-date listing of public waterbodies that are categorized as being under a Watch, Warning, or Hazard label. That listing can be found here: https://www.kdheks.gov/algae-illness/index.htm.