At the neighborhood scale, detention basins are constructed to collect stormwater runoff, thus slowing the water’s travel time to the streams or allowing for increased infiltration to the groundwater system. The link between the basin and the pipe network to the streams is usually a concrete structure with various shapes of weir outlets. Design of these outlet structures are generally based on empirical, flat-plate weir equations that rarely resemble the outlets they are meant to represent.  Additionally, many of these outlets are not simple rectangles or triangles, and these non-traditional configurations create momentum changes that are unaccounted for within the classic weir equations. More research is needed to improve on the weir equations so that they accurately represent thick-walled, non-traditional shapes.