Three‐Dimensional Eutrophication Model of Chesapeake Bay

Abstract

CE‐QUAL‐ICM is a three‐dimensional, time‐variable, eutrophication model. CE‐QUAL‐ICM incorporates 22 state variables that include physical properties; multiple forms of algae, carbon, nitrogen, phosphorus, and silica; and dissolved oxygen. The model is part of a larger package that includes a three‐dimensional hydrodynamic model and a benthic‐sediment diagenesis model. Application to Chesapeake Bay over a three‐year period, 1984–86, indicates the model successfully simulates water‐column and sediment processes that affect water quality. Phenomena simulated include formation of the spring algal bloom subsequent to the annual peak in nutrient runoff, onset and breakup of summer anoxia, and coupling of organic particle deposition with sediment‐water nutrient and oxygen fluxes. The study demonstrates that complex eutrophication problems can be addressed with coupled three‐dimensional hydrodynamic and water‐quality models.