b'GENERAL INFORMATION Below ground wastewater and stormwater sewer piping require Below ground wastewater and stormwater sewer piping require access openingsaccess openings at certain at certain intervals to allow for access, connection points, and change-in-directionintervals to allow for access, points. A Manhole is used for these activities. The Manhole is a belowgroundconnection points, and change-round or square structure made of precast concrete. Sewer piping connects nearin-direction points. A Manhole is the bottom of the manhole structure. At the street level, an iron access cover used for these activities.(often referred to as a manhole cover) is placed to permit access.Sanitary Sewer Manholes: This manhole is used on sanitary sewer lines for the conveyance of sanitary sewer. The Sanitary Sewer Manhole is typically 48-inch diameter and varies in depth according the depth of the sanitary sewer. At the bottom of the manhole and at the pipe connections of the sewer, a channel(also called an invert) is formed so that the sewer flow is smooth and unimpeded. Since sanitary sewer can be corrosive, interior liners can be specified to the manhole interior.Stormwater Manholes: This manhole is used on stormwater sewer lines for the conveyance of rainwater. The Storm Sewer Manhole is generally characterized by a larger size, which is dictated by the sewer pipe connection sizes and orientation. Sizes of Storm Sewer Manholes can range from 48 inches to 120 inches in diameter and will vary in depth according the depth of the storm sewer.182'