National Grid and nearly 50 other pipeline companies are joining to present a nationwide "811 Day," which serves as a reminder for anyone planning a project that includes digging, boring, trenching or excavating to call 811 to have underground utility lines marked prior to any digging project.

"Excavation projects damage an underground utility line every three minutes in the U.S.," according to National Grid. The company recorded more than 1,500 instances of damage to underground equipment by third parties last year. These "dig-ins" are the leading cause of natural gas leaks.

State laws mandate that 811 be called several days in advance of beginning projects that require excavation. Failure to call 811 may be punishable by fines, which in some states can be as high as $1,000 for a first offense and $10,000 for subsequent offenses.

"What may appear to be a simple job can jeopardize public safety if you don’t plan ahead and make a call to 811," said, Karen I. Klimas, National Grid’s vice president of Safety, Health and Environment. "A single phone call can potentially avert a tragedy. We’re hoping this campaign will bring home the importance of that 811 call."