Figure 2: Cross Section profile of the 27891.3 cross section after dam removal

Figure 6: The cross section profile for the after dam removal analysis at the dam cross section, showcasing the different flooding. 

Figure 5: The cross section profile for the before dam removal analysis at the dam cross section, showcasing the different flooding. 

Figure 4: The Water Surface Profile for the after dam removal analysis, showcasing the different flooding. 

Figure 3: The Water Surface Profile for the before dam removal analysis, showcasing the different flooding. 

Figure 1: Cross Section profile of the 27891.3 cross section before dam removal

Table 2: Table of plans and flows 

Table 1: Table of flow and froude numbers for before and after dam removal for cross section 28791.3

Results 

These figures show that dam removal reduced upstream flooding and eliminated ponding, allowing the river to return to a more natural hydraulic condition with lower water surface elevations and less overbank inundation. For the 100-year flood, water levels with the dam in place were approximately 8 feet above the left bank bed elevation, whereas after removal they were only about 1–2 feet higher. With additional cross-section data, downstream impacts could have been evaluated further; however, based on the available sections, no significant downstream flooding differences were observed.

These profiles show that the ponding effect is eliminated after dam removal and that overall flooding is reduced. Upstream water surface elevations are lower in the post-removal condition, indicating decreased flooding compared to the pre-removal profile. The energy grade line and water surface are more parallel and consistent, reflecting a return to stable, river-like hydraulics rather than impounded flow. Overall, dam removal clearly reduced localized flooding at the former dam site.

The post-removal cross sections indicate a reduction in flow depth to around 2 feet, consistent with commonly reported normal depths for the Maury River.

The increase in Froude number from approximately 0.01 to 1.01 indicates that backwater ponding conditions were eliminated and the flow transitioned toward critical conditions, reflecting a return to a more natural river flow regime.

For the results, Froude numbers were evaluated at the cross section upstream of the former dam location, and downstream cross-section profiles were analyzed to assess changes in flooding conditions following dam removal. These results are subject to uncertainty because only one measured cross section was available for the river reach. While the trends align with findings in existing research, the exact values and profiles may be inaccurate. This analysis is therefore intended as a conceptual example of how river reach behavior can be evaluated when considering the removal of other dams in the future. For reference the following table describes what each of the plans mean:

Disclaimer: This website presents an educational analysis of stream and river hydraulics using HEC-RAS. The modeling is based on simplified assumptions, estimated inputs, and limited available data. All results are for academic purposes only and are not intended for design, regulatory, or implementation use.

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