Comment on “A Model for Total Phosphorus in Saginaw Bay”

The subject paper (Canale and Squire 1976) presents the results of the application of a steady-state mass balance model to chloride and total phosphorus data for Saginaw Bay in 1974. Richardson (1974, 1976) has modeled chloride in Saginaw Bay on both a steady-state and a time variable basis. In this work, the steady-state model was shown to be inadequate for this system, except during stable periods in summer and fall. Since most of the loading of pollutants to the bay does not occur at these times, the time variable model was developed. The purpose of this comment is to compare similar aspects of these projects and to contrast the steady-state and time variable approaches with respect to their ability to simulate observed phenomena and the utility of their results.