Mud Ponds and What I Know About Them

Mud ponds

Mud ponds permit the acquisition of enormous bodies of water, and are indicated if you want to grow enormous numbers of fish, or perhaps just grow a few fish to enormous size.

It’s true that fish are limited by the size of their facilities. In small containers, a five year old Koi may be twelve inches long. In a mud pond, the same five year old fish would be “twenty-something” inches long, surely burgeoning on thirty.

Construction of a mud pond is almost as simple as excavating a large hole and filling it with water. The excavated mud or dirt from the hole is used to build wide levies which raise the edge of the mudpond above ground level, to prevent runoff.

If the pond is desired in an area with well drained soil, it may have to be “lined” with Bentonite clay. After lining the pond with Bentonite clay you can further ensure it’s water-tightness by keeping the pH in the mid sevens to eight.

In many parts of the country; however, clay is abundant and the ponds are just “cut and filled”. Filling a mud pond is really only economically-feasible if you can redirect naturally occurring water or if you can mechanically pump water from a natural source such as river or spring and then put the water into the mud pond.

Another consideration of the mud pond is the ability to drain and clean it. Many mud ponds are installed without these beneficial features, but it’s usually relatively simple to install a large PVC standpipe which allows the pond to overflow at a certain depth. Then, when desired, the standpipe can be removed and the pond drained down to just a few inches. This allows safe cleaning of the pond of bottom debris and is commendable for the pond after a few years of use.


Dr Erik Johnson is a Marietta, Georgia Veterinarian with a practice in small animal medicine. He graduated from University of Georgia with his Doctorate in 1991. Dr Johnson is the author of several texts on Koi and Pond Fish Health and Disease as well as numerous articles on dog and cat health topics.