With spring approaching, many homeowners will tackle home improvement projects, including planting gardens and building fences, or bigger jobs like adding home additions and swimming pools.

However, what you might not realize is that lurking not far beneath the ground surface are all sorts of pipes and utility wires. Cut one of these accidentally and you can see your DIY project turn into a costly surprise.

Here's what you need to know before you start digging.

Don't Ignore the Dangers

You might think there's nothing beneath your backyard grass than a few dozen feet of dirt.

The reality is pretty different.

Depending on where you live, there's a complex system of pipes and wires just a foot or two below your yard, home and driveway. Some examples of what you'll find include gas, sewer and water mains, as well electrical, internet, cable and phone service wires, plus natural gas pipes. Now, you can probably imagine that hitting any of these and knocking them out or damaging them can turn your project into a nightmare. Knowing where these pipes and wires are located is a good first step to avoiding disaster.

Did you know the Federal Communications Commission (FCC) has a phone number you can call to get specific information on where it's safe to dig in your area? While it's not mandatory to call, it's set up for your protection and free for people living in the United States. Before you dig, you can dial 8-1-1 and a specialist will come to your home, mark your yard and show you where the underground service lines and pipes are located.

Making this call can dramatically reduce the risk of cutting wires or pipes while you dig—saving you a big headache and big dollars.

Plan Out Your Project

Before you dive into your project, develop a plan, which can help in two key ways: You can map out the general area where you'll dig and settle on how deep to go.

Begin by creating an outline for your project. It will help things move smoothly and reduce potential delays. When it comes to your outline, start simple.

First, using the information you've received from the FCC, you know where it's safe to dig. Ideally, you want to create a blueprint that will map out your project. While you don't need to go too professional here, it's important to have your drawing to scale. The last thing you want is to accidentally dig two feet too far in one direction and crack a pipe.

Second, figure out the tools you'll need. For most small DIY type projects in the garden, a spade or shovel will do. For more advanced projects, you might need to rent bigger tools like diggers from your local hardware store. If you're handing the project off to pros, make sure you give them any information you received on service line locations.

Lastly, work out a solid time frame for your project. Set aside a few hours to plan out when you'll implement each phase and how long it should take. Don't forget to include the inevitable weather delay—it's spring, after all!

Protect Yourself

Another way to avoid these potential issues is to consider service line coverage. If an accident does happen, it can help cover repair and replacement costs.

Another benefit? Service line coverage can fill the gap that many homeowners have in their current homeowners insurance policy, which often doesn't cover service line damage. Plus, with the costs of damaging a line running upwards of $7,000, it can help give you peace of mind that one small mistake won't turn into an expensive problem.

Spring is a prime time to improve your home—just make sure you're prepared before digging too deep.