*Pond owners notice water level dropping.
*Loosing pond water through evaporation- use a DNR pan test to find out an accurate evaporation rate.
*Damp soil could be a leak. How to fix that.
*Save time and Money by having your leak diagnosed and fixed.
Ponds are notorious for leaking. And leaks can lead to the other big pond problem – algae growth. If you notice your pond water dropping, have to continually fill the pond, or hear the pump “chugging” i.e. running dry, you are loosing water. Here are a few tips from Jeff, the pond pro, about diagnosing for leaks versus evaporation.
Loosing Pond Water Through Evaporation:
All ponds loose water to evaporation. Windy weather, hot temperatures, and amount of plants in and near the water all speed up evaporation. Regional differences also make their mark with western Minnesota experiencing higher evaporation rates than other regions.
To test your rate of evaporation, run a simple “pan test”. Place a bucket or tub with water near your pond’s edge. Measure how deep the water is, record the date and water depth and leave the tub alone. (You may want to protect it from doggy friends taking a drink!) Remeasure the water depth after 48 hrs. Measure again after 7 days. The amount of water lost would be your “evaporation rate” for your location.
When setting up your pan test, also set up a small ruler in your pond. For the most accurate results, leave the ruler in the pond during the pan test and don’t move it. We like to clip a ruler to the side of the pond skimmer or tuck it between rocks so it can’t blow over or fall in the water. Record the date and measurement of the water levels in your pond when your record the pan test results. Note: If your pond has an automatic fill valve, turn this off before running your test! If you don’t know, check the irrigation box nearest your pond.
Evaporation rates are highest July through September in Minnesota. Here are the evaporation rates measured by the U of MN and DNR for the past 53 years. Monthly rates are listed so divide by 4 to find weekly rates. For example, July, 2025 had an evaporation rate of 8.25. (8.25/4 = 2.06 inches per week).
After measuring both your pond and the pan test, compare the results. If they are the same, good! That means your pond is not leaking! But if you find the pond measurements are higher, there is a leak and leak detection must begin. For detailed Leak Detection directions, read “How do I find a Pond Leak?”.
Damp Soil: Another leak sign
You may see damp soil along the edge and worry because “the pond is leaking”. If you touch the soil and your finger slides easily into the earth and fills with water in a few hours, you probably have a leak. This can easily happen if the rubber liner gets pushed down by a rock, a plant, settling soil, or footsteps. Gently tug the rubber liner up and prop it in place with extra soil or rocks. You want the soil 3-6 inches above the waterline to prevent further leaks on the edge.
Damp soil may occur if there is a cut or split in a pipe from the winter freeze/thaw cycle. This type of leak is fast; your pond will be loosing significant amounts of water when the pump is running.
Ponds are fun when they run correctly but frustration easily sets in when silent leaks are present. If you just “want the pond to look good” and don’t have time to find leaks, feel free to call us. Our tech team can help spot potential leaks, run pressure tests on piping, and repair broken parts saving you time and money.
Written by: Jeff & Becky Chudek- Minnesota Waterscapes Feb. 2026