To ensure that you remain safe when doing any digging projects, always call 811 first. 811 is a free service managed by Underground Service Alert and available to everyone. After you call, Underground Service Alert will contact companies that have underground lines in your area. Representatives will then mark the location of their underground lines so you can avoid them and dig safely. Whether you are planting a tree or a garden, or digging holes for fence posts, call 811 at least two business days before you plan to start your project. For more information visit California 811Opens in new Window..