Experimental and numerical investigation of water depths around a manhole under drainage conditions

This study uses a physical model to quantify shallow water depths around a scaled manhole during drainage (surface to sewer flow exchange) conditions and through a scaled manhole. A series of tests have been conducted within an experimental facility over a range of steady-state (flow exchange rate) conditions. The datasets have been used to validate both a 2D Finite Volume Model and a 2D Finite Difference Model. The results show a very close agreement between experimentally observed and numerically modelled flow depths irrespective of the flow exchange between the surface and the sewer system. The results provide increased confidence on the reliability of these two numerical methods to model surface to sewer flow under different steady state hydraulic conditions.