Can you dig it? Call 811, the national Call Before You Dig number, at least 48 hours before you start to dig. Utilities will mark the power lines, pipes, or cables buried on your property. With just one call, you can stay safe and prevent needless outages. It's easy. And it's the law. otpco.com OTTER TAIL POWER COMPANY Can you dig it? Call 811, the national Call Before You Dig number, at least 48 hours before you start to dig. Utilities will mark the power lines, pipes, or cables buried on your property. With just one call, you can stay safe and prevent needless outages. It's easy. And it's the law. otpco.com OTTER TAIL POWER COMPANY