A computational framework is presented to evaluate the stability of two inlets connecting the same bay to the ocean. It is assumed that both inlets are scoured in alluvial material. The main ingredients in the stability analysis are the closure surface and the equilibrium stress surface. The closure surface of an inlet is defined as the relation between the tidal maximum of the bottom stess and the cross-sectional areas of both inlets. The equilibrium stress surface of an inlet is the relation between the tidal maximum of the bottom stress and the cross-sectional area of that inlet at the time the inlet is in equilibrium with its hydraulic environment. The method is applied to Pass Cavallo and the entrance to the Matagorda Shipping channel further referred to as Matagorda Inlet. Both inlets connect Matagorda bay to the Gulf of Mexico.