Colored Flags in the Grass Before Anyone Digs
Under a typical neighborhood lies a hidden web of pipes and cables. Some carry electricity or natural gas. Others bring in drinking water, carry away waste water, or hold telephone and internet lines. Because nobody can see them, a shovel can hit one by surprise.
To prevent that, the United States has a single phone number for anyone planning to dig: 811. A person who calls explains where the hole will go. The call is free, and the request is passed to the companies that own lines in that area. Each company sends a worker to mark where its lines run.
The markers use paint or small flags, and each color has a meaning. Red usually shows electric lines. Yellow warns of gas. Orange marks communication cables, blue shows drinking water, and green points to sewers. White outlines the spot where the digging will happen. Workers often need a few days to finish, so people are asked to call ahead instead of grabbing a shovel that afternoon.
Calling is the right thing to do, and in most places it is also the law. A broken gas pipe can be dangerous, and a cut cable can leave a whole street without power or internet. The rule protects the person digging and everyone who depends on the lines nearby. A free phone call saves neighbors a lot of trouble.