Section Env-Wq 704.16 - Manholes: Drop Entry Construction Requirements(a) The invert of the incoming pipe shall be no more than 6 inches above the invert of the outgoing pipe unless a drop entry pipe is used.(b) Sewer slopes shall be adjusted to avoid differences in incoming and outgoing pipe inverts greater than 6 inches unless a drop entry pipe is used. Invert differences greater than 6 inches and less than 24 inches shall be eliminated by adjusting the sewer slope.(c) A drop entry pipe shall be provided for any sewer entering a manhole at an elevation of 24 inches or more above the manhole invert. The drop pipe may be constructed internal or external to the manhole.(d) The maximum size limits and number of internal drop pipes within a manhole shall be as shown in table 704-6, below: Table 704-6: Size Limits and Number Requirements for Internal Drop Pipes
Manhole Diameter | Internal Drop Pipe Size | Number of Pipes Required |
4-foot, 0-inch | 8-inch or 10-inch | 1 |
5-foot, 0-inch | 15-inch | 1 |
8-inch or 10-inch | 2 |
N.H. Code Admin. R. Env-Wq 704.16
Adopted byVolume XXXIV Number 46, Filed November 13, 2014, Proposed by #10693, Effective 10/15/2014, Expires10/15/2024.