Before you put the shovel in the ground to plant anything, you should know what is below the soil surface. The biggest threat of damage to underground utility lines occurs when planting. Water pipes pose a problem because they may be buried quite close to the surface. Rupturing one will cause a flood, disrupt the water supply and cost a lot of money to fix. Trees often have roots that are much larger and widespread than expected. These roots can disrupt water pipes that sit up to 100 feet away. No matter the size of the plant you're putting in the ground, you need to plan in advance so you can avoid damaging water pipes.
Call the local utility company at least three days before you want to plant something on your property. Arrange for someone to come by and show you where the utility and water lines are located. They should do so at no cost to you.
Consult a topographic map of your property. You usually get a copy of your property map when you purchase a home. It will show the measurements of your property and where all structures sit.
Buy an appropriate plant for the planting area. Roots tend to grow toward a water source, even if it's underground water lines. It's essential to choose a plant that has a deep root system as opposed to a shallow, spreading habit.
Avoid planting anything right above markings that signify a water line. Use the estimated mature canopy size as a guide to determine how far the roots will spread. Usually root growth mirrors the canopy growth above ground.
Allow 100 feet between a tree and water line if you choose trees such as willows, poplars, rubber trees, figs or eucalyptus trees. Their roots will seek out water sources up to 100 feet from the tree trunk.
Dig a hole once you're sure it is a safe distance from the water pipes. Make the hole twice as wide as the root ball, and place the tree in the center. Backfill the hole with the removed soil and water until moist.