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Q: When using the "J" junction type manhole which losses / equations are applied? A: When using the Engelhund method, the J type 'manhole' uses the same equations as for the R and C type manholes in for the losses associated with change in direction (K-theta) and change in elevation (K-drop) at the junction. However, for expansion and contraction losses at the junction, these are recalculated every timestep according the departure/approach velocities of the downstream/upstream culvert (see Equations in Section 4.7.4.1 in the 2010 manual. These equations are essentially the same as used the manhole expansion/contraction losses, however, instead of using the manhole area for the term Am, the area of the downstream/upstream culvert is used. The applied entry and exit losses at a J 'manhole' are therefore a function of the approach and departure velocities which are derived from the incoming and outgoing pipe respectively. The calculated losses throughout the simulation can be reviewed in the _TSL output layer.