A sewer grate is a grate that covers the entrance to a ground level sewer line, which allow water to enter the sewer. These can be small or large, depending on where they are placed. Small sewer grates are often used on residential properties, while larger ones are typically used on public roadways. Today, most sewer grates are made from strong metal, and many of them are circular.
The entrance to a sewer line is usually covered with a sewer grate. These grates usually fit into an inset lip at the entrance to the sewer line. Holes in the grate allow water to pass through, into the sewer. Larger debris, such as twigs and trash, are usually caught by the grate.
When a sewer grate accumulates a large amount of debris, it must be cleared out. If debris is left to sit on the grate, it could clog it. When these drainage grates become clogged, water pools around the entrances to the sewers.
A small sewer grate may be used on residential properties, especially those that are prone to flooding. These are often used to cover drainage pipes. Large sewer grates, sometimes referred to as manhole covers, are the grates that can be found on roads and highways. Everything that drains down into these sewers usually ends up in the public sewer system.
Although they are heavy and cumbersome, large manhole covers are stolen right from city streets. A thief is sometimes able to sell a metal sewer grate as scrap. A missing manhole cover can be very expensive to replace, not to mention dangerous.
Besides keeping debris out of the sewer, a sewer grate has another important function. It ensures that people and animals do not fall into larger sewer lines. If this happens, it often results in injury or even death.
Over the years, sewer grates have been made from a couple materials. A sewer grate from ancient Rome was found to be made of stone. Steel and iron are two of the most common materials used to make sewer grates today. Steel is usually used to make smaller grates, which can hold less weight. Iron, on the other hand, is typically used to make much larger grates, such as those found on city roads.
Today, most manhole covers and sewer grates are round discs, and there are a couple reasons for this. It is more likely for a square sewer grate to fall into a sewer line than a round sewer grate. Round metal discs also cost less to manufacture, and they are easier to move. Some cities in the United States still have unusually shaped trianglular manhole covers, but these are slowly being replaced.