I want to plant some tall grasses about 3 feet from an electrical pad transformer in my yard. Do I need to call the utility companies before digging? I will only be digging one foot down. Are the electrical lines that close to it in a conduit?
You have to call the utility to get a locate on the lines. Every electrical utility can have different standards.
Practically speaking, if you gently hand dig you should not have a problem. If you do so you take all the potential risk for accidents and mishaps so this is why I recommend using the free locate services that many utilities offer.
Edit:digging near lines is a job worthy of some thought. My experience in Ontario has been:
- phone lines: can be found anywhere, on the ground, in the ground, hidden, in plain view
- natural gas lines: usually three to six feet down and strong enough that hand digging will not break them. If you do break a line you take your chances at blowing up your house and, possibly, every house connected to that line on the block.
- sewer or drain: usually six feet down or under the frost line and strong enough that you need to be using power tools or machinery to break them. If you break them you could be liable for the repair costs or more.
- hydro/electrical: lines are usually encased in three inch diameter PVC pipe and are usually buried under the frost line. Depending on where you live this could be as little as two feet to three feet. They rise to the surface where they connect to box or house.
- cable lines: usually buried in three inch diameter PVC pipe and buried underground or run on phone poles. Anywhere is a possibility.
I've planted right over the top of mine, and many people in my neighborhood do. For my plantings near the lovely green box, I hand dug down about a foot and never saw any sign of wires. For the foundation plantings I put in near my house, I accidentally unburied a pvc pipe with wires that was about 2 inches under the surface. Since I was digging with a hand trowel, I didn't do any damage to it. I just reburied it and moved on to another spot. Your mileage, of course, may vary.