Estimated Flooding from Hypothetical Flow Conditions on the Lower Fox River, Wisconsin.

Basic hydraulic data, such as water-surface elevations, discharges, and peak arrival times, have been calculated for the Lower Fox River to aid in estimating hypothetical flows created by the Probable Maximum Flood PMF without dam failures Case 1, the PMF with dam failure Case 2, and dam failures with low inflow with pools at or near the spillway crest elevations Case 3. This study was part of a national program to conduct similar studies of all Federal dams. The selected situations are strictly hypothetical for representing maximum flooding conditions, and the results are not in any way intended to adversely reflect upon the integrity of the 13 existing dams on the Lower Fox River. Study results are reported in the form of computer printouts, tabulated data selected from the printouts, and hydrograph plots for various points along the river. Inundation maps specified in the HEC Guidelines will be developed by the U.S. Army Engineer District, Detroit, to clearly depict the anticipated extent of flooding, peak stages, and flood arrival and peak times at key locations in the floodplain. A numerical model named Branched Implicit River Model BIRM, which was developed by the U. S. Army Engineer Waterways Experiment Station for forecasting flows on the Lower Mississippi River, was employed for this study to simulate the selected hypothetical flow conditions.