(a) Grade; Bends. Sanitary sewerage lines shall have a uniform grade and be straight between manholes. No bends will be permitted between manholes.
(b) Minimum Size. No sewerage line extension shall be less than six inches in diameter.
(c) Depth. Minimum depth of sewers shall be as approved.
(d) Slope. All sewers shall be so designed and constructed to give mean velocities, when flowing full, of not less than two feet per second. The following are minimum slopes to be provided:
Sewer Size | Minimum Slope in Feet Per 100 Feet |
6 inch | 0.60 |
8 inch | 0.40 |
10 inch | 0.28 |
12 inch | 0.22 |
(e) Erosion Protection. Where velocities greater than fifteen feet per second are obtained, special provision shall be made to protect against displacement by erosion and shock.
(f) Manhole Location. Manholes shall be installed at the end of each line; at all changes in grade, size or alignment; at all intersections; and at distances not greater than 400 feet. Lampholes may be used for special conditions, but shall not be substituted for manholes or installed at the end of laterals greater than 150 feet in length.
(g) Drop Pipe. A drop pipe should be provided for a sewer entering a manhole at an elevation of twenty-four inches or more above the manhole invert.
(Ord. 870. Passed 2-3-64.)