Two regression equations describing water movement in saturated macropores in the field are compared with a theoretical expresion of the form Q_maα e²_ma where Q_ma is the saturated volume flux density through a macropore system of porosity e_ma. The theoretical exponent of 2 agrees fairly well with the analyses of two very different sets of field experiments by Burger (1922–1940) and Ehlers (1975). It is suggested that the relationship Q_ma= Q*e²_ma may be a useful first approximation to predict macropore flow, where Q* is an empirical coefficient that is expected to depend on the hydraulic connectivity, geometrical structure, tortuosity, roughness and other properties of the macropore system.