Underground springs can be pleasant or problematic to have in the yard. If your grass or soil is constantly wet, even when the surrounding areas have been dry, you may have an underground spring. It is also possible you have broken pipes, or a buried water well. Detecting springs involves observing many indicators around a given area and then conducting a physical examination. You can detect the location and size of the spring using these methods and it may take several days, because all signs may not present themselves at the same time.
Examine the density and abundance of plant life in the area. Dense, healthy and abundant groups of plants located in an overgrown location, compared to the surrounding vegetation, may indicate underground water. Look for unusual amounts of growth in areas normally dry or sparsely vegetated. Examine the color of the vegetation. Brighter and more vibrant colored plants are found in areas where water is directly available.
Look for animal tracks within the same area. Tracks leading to and from the area from different directions indicate animals are migrating to known water sources.
Watch for high levels of insect activity in the area. Insects seek out surface water for nourishment. Water near the surface will attract insects. High amounts of gnats and mosquitos indicate standing water.
Observe the behavior of the birds. Birds feeding on insects will congregate around the area seeking food. Early morning and late evening will show a greater quantity of birds also seeking fresh water.
Look at the ground for worms, garden snakes and other invertebrate species. Worms love moisture, as do snakes. Areas where a constant source of water is found will show an abundance of these creatures.
Step firmly onto the surface. If the ground feels soft or springy it is oversaturated. The oversaturation may be a sign of an underground spring. Observe the ground as you step looking for water to seep up as it would if you squeezed a sponge. If the ground is muddy, consistently wet, or has pools of water without any natural explanation of their source you may have an underground spring.
Remove standing water with a shovel. Dig into the soil a few inches. Watch the area for water seeping back onto the surface.
Locate underground water pipes, wells or water holding tanks. Check those in the vicinity for damage. If you have no water source, damaged or otherwise, nearby, you may have an underground spring.