A guide to building and maintaining healthy ponds and small lake ecosystems for your residential home or farm
When deciding to construct a pond, landowners might look for a location where it would be most convenient or picturesque.
But with many other technical factors to consider, such as the geological makeup belowground, rain runoff, and others, it’s advisable to enlist the expertise of agencies and others with experience and research to help make that decision an informed one.
The Kentucky Department of Fish and Wildlife Resources in Frankfort manages fishery resources statewide and serves as the regulatory branch for fisheries, conducting research that helps shape future regulations.
“We specialize in sport fish management and there are a number of sport fish species in the state, whether we stock them or they occur naturally,” says Kerry Prather, a recently retired central fishery district biologist.
In all, there are about 250 species of fish in Kentucky, mostly nongame fish living in streams, he says.
When it comes to pond problems, Prather explains that the most common mistakes include improper construction, choosing the wrong location, and improper stocking.
If a pond is built too small with too large of a watershed draining toward it, the dam can fail. If the watershed feeding the pond is too small, the water will be very clear and slow to fill, with an overgrowth of aquatic plants and limited fish growth.
The Natural Resources Conservation Service can also help recommend suitable pond locations, Prather adds.
As for stocking, the KDFWR has recommended methods of keeping fish populations in balance so they live harmoniously and both support and control one another. They also offer stocking services, and people who use them are under no obligation to allow the public to fish there, a common misconception, Prather says.
And if there are problems, the department accepts questions from the public, or for persistent issues, a site visit can be performed with a technical guidance program consisting of a biologist and fisheries crew.
Jeff Crosby, who succeeded Prather as a fishery biologist for the central district, says they check basic water quality parameters, evaluate the fish population, and assess the problem at no charge. This is usually done in late spring to early fall, avoiding the hottest weather when possible, and as staff schedules allow.
Richard Durham is an associate Extension professor with the University of Kentucky and coordinator of the Kentucky Extension Master Gardener Program. He provides training for county Extension agents for horticulture, including some pond-related topics.
He notes the Extension service’s horticulture division only works with landscape or decorative fish ponds, not farm or agricultural ponds.
“The biggest problems that we hear about are in spring,” says Durham. “People’s ponds inevitably turn green because of the biology going on.”
This problem is usually self-correcting, he says, and results from the leaf and fish waste being broken down by bacteria, which are not as active in the winter and flourish in the spring, but their activity tends to wane as the wastes are consumed and the water clears.
Some preferable pond plants like water lilies, water lettuce, and water hyacinth need at least six to eight hours of sunlight per day, Durham says, and sometimes won’t thrive if they’re in a shady area. He adds that water lettuce and water hyacinth are not recommended for use south of Kentucky, as they tend to become invasive in warmer climates. He also advises that ornamental ponds be no more than 2 feet deep to allow fish to survive over the winter.
Bardstown resident Jack Newcomb has three ponds at Stone Creek Farm, which has been in his family for about 16 years. Two ponds are 4-1/2 acres each and one is a lake-like 29 acres, he says. The farm has row crops and dairy heifers.
All man-made bodies of water, the smaller ponds were constructed 12 and 15 years ago, and the largest only five years ago.
He, his friends, employees, and family use the ponds for fishing, swimming, and canoeing. Aside from the water levels being down on the ponds a bit from a dry summer, they’ve had no problems.
Newcomb’s home is built at the edge of the largest pond, and he said it’s a spectacular view.
“You can go out and feed the fish off the back porch,” he says.
Another pond owner is Robert Marshall of Shelby County, and he says constructing his pond was the easy part.
“It took two bulldozers about a week,” he says. “I had to clear a lot of trees out.”
He had owned the 10-acre site for about 15 years, and about six years ago decided to create a 3/4-acre fishing pond near the back of his tract for fishing. It’s about 700 feet from his home.
After stocking the pond with channel catfish, largemouth bass, bluegill, and crappie obtained from the Kentucky Department of Fish and Wildlife Resources, he waited about five years to allow fishing so the fish could grow.
Marshall was enjoying his pond in earnest, and by this time had built a “pond house” with a deck, where he holds parties and cookouts.
But just underneath the surface of his pond’s waters, disaster lurked—at least for the fish.
Last year, the pond “turned over,” or more technically, became oxygen depleted, enough to kill many of the big fish.
In hindsight, Marshall figures he should have allowed fishing a bit sooner to thin out their ranks.
“That’s one of the reasons it turned over,” he says. “It had too many fish in it.”
Department literature on pond management also cites the oxygen produced by microscopic algae as crucial to pond oxygen levels.
Marshall spent $6,000 for an aeration system to remedy the situation. It consists of an air pump that blows air through 18 diffusers under the water. The system is set to run on a timer just two hours a day.
The system protects the well-being of surviving fish, as well as the fish he purchased from a private company to replace the bass, catfish, and larger bluegill that were killed off.
Earlier last summer, Kentucky Department of Fish and Wildlife Resources staff helped Marshall assess the types of fish in his pond and stocked it again with proper levels of different species.
Now he has to wait a bit longer for the fish to grow before he fishes again, but he continues to make use of the pond house and enjoys his pond immensely.
“I wouldn’t take anything for my pond,” Marshall says. “It’s peaceful and quiet and nobody bothers me.”
DIGGING DEEPER INTO PONDS
- Pond uses can include domestic water supply, irrigation, fire protection, wildlife habitat, water source for livestock, recreation, and fish production.
- To properly maintain fish in a pond, it should have a minimum average depth of 6 feet and a maximum depth of 12-15 feet. Ponds should not be smaller than 1 acre, or the fish population balance will be harder to maintain.
- Ten to 15 acres of surface drainage are required for a 1-acre pond to stay filled and thriving; shoreline depths of 2-3 feet or more are ideal to prevent aquatic weeds from overgrowing.
- New ponds located on a site with karst geology, sinkholes, springs, and limestone formations may not hold water.
- Stocking ponds with fish caught elsewhere or dumping bait fish into a pond is not recommended, as it can lead to an imbalance of fish species or introduce undesirable species. Invasive fish species include green sunfish and bullhead catfish.
- Fences can be used to keep livestock out of a pond, while planting shrubs, hedges, evergreens, and certain grasses can help wildlife habitats and create a natural buffer area.
- Experienced pond-building contractors should be consulted once the decision is made to create one. “Make sure and check references,” advises Jeff Crosby, Kentucky Department of Fish and Wildlife Resources’ central fishery district biologist. Other considerations when building a pond include use of pesticides and herbicides on nearby land, other nearby ponds that may contain undesirable fish species, and the capability to control water levels—the Kentucky Department of Fish and Wildlife Resources can provide information on all these issues.
KEYWORD EXCLUSIVE: GO FISH
For a list of signs that point to problems with a pond’s fish population—too many fish, too few, wrong species—that should also help keep your fish from going belly up, go to go fish.