Managing Iowa Acreages: Protect Your Pond

Whether your pond was built to stop gully erosion, provide water for livestock or become a great fishing hole, it is now your job as a pond owner to maintain it. A pond has a natural ecosystem. When managed properly, it can offer wonderful recreational and environmental benefits, but when the natural balance is disrupted it can be an unsightly eyesore.

Pond maintenance involves inspecting different areas of the pond on a regular basis for signs of erosion, structural integrity, water quality decline, wildlife damage and aquatic weed control. Complex problems, such as a leaking pond, may require the assistance of a licensed engineer. 

The spillway and the dike, or dam, are the two most significant features which need regular inspection. The spillway guides water to an area where flow won’t compromise the dam or other pond structures. This structure is key to preventing failure of the dam. When inspecting the spillway (and the dam), make sure there is no woody vegetation. The root systems can weaken the structure. You’ll also want to check for damage caused by burrowing animals.

Monitor the dike or dam for unusually soggy ground near the base, muddy water seeping through the dike, rills (long channels in the soil), soil slumping down the dike and washouts. Also, water can seep along the outside of a spillway pipe, carrying away soil and creating a hazard.

You should also closely monitor the pond for bank erosion. An unexpectedly heavy rain or spring thaw can intensify a small erosion problem without warning. Steep shores without vegetation can erode to cause cloudy water conditions and pond silting.

Pond owners should check the dike and side of ponds carefully several times a year. Establishing good grass cover helps prevent erosion on the exposed areas near and around a pond. Fill eroded areas and re-seed or place sod over bare soil. The roots will retain and stabilize the soil. If needed, use a temporary seeding of rye grass or other quick growing cover if it’s too late in the year for good grass establishment.

Depending on location, pond water may have a natural green, olive or brown color. If you are concerned about cloudy water, it is important to determine the cause. Possible causes include shore erosion and runoff from nearby land, algae or plankton. Fill a tall jar with the cloudy pond water and inspect it under bright light. Algae or plankton will appear as green flecks or tiny moving organisms. If the cloudy conditions settle after a few days, the pond likely has a siltation problem.

Pond plants provide many benefits, including prime fish habitat, shade, erosion control, oxygenation and scenic beauty. Become familiar with the plants in your pond and determine if or when a plant is overabundant. If plants are interfering with common uses of a pond (fishing, swimming or irrigation), they should be identified and treated.

Many methods of aquatic weed control are available. Before selecting a treatment, determine if excess nutrients are entering the pond from a septic tank, agricultural operation or treated lawn. Substances like nitrogen and phosphorus create algae blooms and excessive plant growth. Nutrient sources should be controlled through careful management and/or buffers before implementing aquatic weed treatment, like weed pulling, herbicides or other environmental controls.

Floating weeds like duck weed and algae masses can be removed from the surface with a skimmer or rake. Aeration is an eco-friendly, cost-effective, preventative and maintenance measure for these issues. Bottom barriers, hand-pulling of root systems and grass carp can be used to reduce submerged plant growth. Additionally, most ponds can be partially drained in the winter to kill aquatic weeds near the shoreline without disrupting fish and wildlife. However, carefully consider the pond depth to avoid winter kill of fish.

Want to Build a Pond?

Not all acreages are suitable for a pond. If you are interested in building a pond on your property, here are a few considerations:

• The site must be suitable in terms of soil and geology to hold water.
• The source of the water must be adequate.
• The pond must be properly managed.

Visit your local USDA-NRCS office to speak with a conservationist about building and managing a pond.

Pond Maintenance Checklist

After storms or heavy rains:

• Inspect dike for erosion and leaking.

• Inspect quality of water entering the pond and reduce nutrient input, if present.

Monthly:

• Assess presence of pond plants; excessive growth typically occurs in mid- to late-summer.

• Maintain mown grass to stabilize dike; remove woody vegetation from dike.

• Check water temperature for fish habitat.

Seasonally:

• Inspect for wildlife damage.

• Repair or replace safety signs.

• Catch fish to determine population health.

• Inspect spillway for stability.

• Inspect fencing to restrict livestock from entering water.

Annually:

• Assess silting or changes in pond depth.

• Record maximum/minimum depths.

• Check water pH and adjust for fish habitat.

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