N.H. Code Admin. R. Env-Wq 1015.02
Velocity reducing devices such as an elbow or "T" shall be installed within the distribution box where the effluent line from the septic tank has a slope in excess of 10% or where effluent is being pumped from the septic tank to the distribution box.
Source. (See Revision Notes #1 and #2 at chapter heading for Env-Wq 1000) #11184, eff 10-1-16; ss by #14486, eff 2-1-26, EXPIRES: 2-1-36