Lowering pond's water level to prevent winter drawdown
Wednesday, October 10, 2012 1:00 AM
Most people think of pond fishing and management as a warm weather affair, but there is much to do (and catch) during the cooler months of the year.
One effective winter management technique requires relatively little effort and offers many benefits to the pond owner.
This is the winter drawdown.
Water level drawdown during winter months is an excellent management technique to prevent or correct overcrowding of prey fish and to reduce nuisance weeds in ponds.
The water level in the pond is lowered in late-October to about one-half the original pond volume.
This is easiest in ponds that have mechanical drains or standpipes that can be adjusted for height.
Smaller ponds can be pumped down, or siphoned using long hoses with variable success.
Usually, water levels are reduced enough to expose 35 to 50 percent of the pond bottom.
Generally, this is about a 2 to 4 foot reduction in water level, but this may vary depending upon topography and design of the pond.
Maximum drawdown should be accomplished by mid to late November, and the water level should remain low into February. Spring rains will fill the pond.
Winter drawdown is a good fish population management technique in largemouth bass/bluegill ponds.
By reducing the water level and pond area, forage fish, such as bluegills, are driven out of shallow water refuges and concentrate in open water, making them more available for bass to eat.
This is a good technique to use in ponds that have "crowded bluegill," but still contain bass.
Bass eat lots of bluegill during the winter, and fewer small bluegill remain to compete for food resources.
Thus, the remaining bluegill grow faster.
Likewise, crowding bluegill makes them more available for bass to eat, resulting in bigger bass.
Routine annual drawdowns can help maintain a balanced bass/bluegill fishery.
Other benefits of water level reduction include allowing terrestrial vegetation to grow on exposed areas during the winter, which when flooded in the spring provides shelter and prey to newly-hatched fish.
However, drawdowns can make bass-crowded situations worse.
If you have a bass-crowded pond, you'll need to consider correcting the problem and do not use winter drawdowns until pond balance is restored.
Ask your county Extension office for assistance with correcting a bass-crowded pond.
Winter drawdown also helps control certain aquatic weeds by exposing them to freezing and drying.
Problem species like pondweeds and hydrilla do not handle dry and cold conditions and will die back, and more-tolerant species can be treated more easily with herbicides when they are dry and exposed.
If necessary, deepen the shoreline to 3 feet deep while water levels are reduced.
This will reduce the likelihood of weeds returning.
Winter drawdown also provides a good opportunity to do repairs on piers, docks, and boat ramps, as well as minor dam repairs and shoreline renovation.
Fish attractors, such as brush tops and gravel beds, can be more easily put in place while the water is down, and this is a good time to deepen edges to the recommended minimum depth of 3 feet.
You can use dirt from the shoreline-deepening operation to build earthen piers at various locations around the pond. These piers increase the shoreline area of the pond and provide increased access for anglers.
Winter drawdown can be a useful tool for the farm pond manager if done properly.
It poses no threat to the fish population and costs nothing if the pond is equipped with a water control structure.
Drawdowns should be done only in the winter, however, never in summer!
The extreme temperatures in Mississippi summers, coupled with the increased activity level of fish and reduced oxygen levels in warm water, likely would result in fish kills during a summer drawdown.
Allow the pond to refill naturally for watershed ponds or manually fill levee ponds beginning at the end of January.
For more information on winter draw downs, request Publication 1428 "Managing Mississippi Farm Ponds & Small Lakes" from your county Extension office.