Certain element types on Screen 3 are grayed out, such as headwater elements and junction elements. This means those types or fields cannot be changed. The only element types or fields that can be changed are the standard elements where the Ss are located. The standard elements could be further defined as point sources, withdrawals, or dams. The user should indicate the locations of point sources, withdrawals, or dams if they are applied.
River reaches and computational elements are the basis of most data input.
Screen 4 is used to identify water quality parameters to be simulated. As mentioned previously, QUAL2E can simulate up to 15 water quality constituents in any combination desired by the user. If either the phosphorus cycle or the nitrogen cycle is not being simulated, the model presumes they will not limit algal growth. The model simulates ultimate BOD in the general case. Geographical and climatological data are entered on Screen 5.