(a) Where it is necessary to make a change in direction of a house sewer between a building and the public sewer, such change of direction shall be made by means of a manhole to be constructed as the Commissioner of Public Works and Streets or his or her designated representative directs.
(b) All manholes and gravel basins shall be constructed of concrete, either monolithic or block, composed by volume of one part of Portland cement, two parts of sand and four parts of gravel or crushed stone, mixed with sufficient water. They shall be circular in section, with an interior diameter of three feet, except that the top shall be drawn into two feet beginning at a point three feet below the top so as to fit and support the cover. The walls of such manhole or gravel basin shall be four inches in thickness if built monolithic, or five inches if built of blocks, with full joints of mortar composed of one part of Portland cement to two parts of sharp clean sand, mixed with sufficient water. Each manhole or gravel basin shall be provided with a six-inch concrete floor with the invert, if any, molded smoothly in the concrete or formed of sections of vitrified pipe imbedded in the concrete. Each manhole or gravel basin shall be provided with a cast iron cover.
(Ord. 1975-15. Passed 11-10-75; Ord. 1995-16. Passed 5-22-95.)