Modeling Complex Tidal Flow Dynamics in the US Army Corps of Engineers Hydrologic Engineering Center’s River Analysis System (HEC-RAS): Assessing HEC-RAS as a Suitable Model in Terms of Accuracy and Speed in Bay and Estuarine Systems

Authors

William H. CampbellFollow

Document Type

Thesis

Degree

Master of Science (MS)

Major/Program

Civil Engineering

First Advisor's Name

Dr. Arturo Leon

First Advisor's Committee Title

Committee chair

Second Advisor's Name

Dr. Hector R. Fuentes

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Dr. Jayantha Obeysekera

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Dr. Gaurav Savant

Fourth Advisor's Committee Title

Committee member

Keywords

HEC-RAS, hydraulic modeling, tidal flow dynamics

Date of Defense

6-19-2023

Abstract

This thesis investigates the use of the Hydrologic Engineering Center’s River Analysis System (HEC-RAS) as a hydraulic model capable of modeling the complex tidal flow dynamics of bay and estuarine systems. HEC-RAS was used to model two complex, tidal-dominated systems: Cook Inlet in Alaska, and San Francisco Bay in California. Simulations were run with only stage hydrograph boundary conditions based on water surface elevation (WSE) data observed by tidal gages and results from the simulation were compared with observed data from tidal gages throughout the studied systems. Additionally, this study investigates the importance (magnitude) of each term of the Shallow Water Equations (SWE).

The results show that HEC-RAS was able to provide suitable SWE results in San Francisco Bay as quantified through the Root Mean Square Error method using observed data. Results in Cook Inlet were not as accurate as San Francisco Bay; however, they showed promise for the potential of high accuracy results, achieving an acceptable level of correlation despite being a far more complex system. Further studies may address this case and find the capability of high accuracy results. Additionally, the quantification of the SWE terms yielded conclusions about the shortcomings of the Diffusion Wave (DW) Approximation when applied to bay and estuarine systems. The Full Momentum model, however, was found to yield highly accurate results.

Identifier

FIDC011148

ORCID

https://orcid.org/0000-0002-7379-4978

Recommended Citation

Campbell, William H., "Modeling Complex Tidal Flow Dynamics in the US Army Corps of Engineers Hydrologic Engineering Center’s River Analysis System (HEC-RAS): Assessing HEC-RAS as a Suitable Model in Terms of Accuracy and Speed in Bay and Estuarine Systems" (2023). FIU Electronic Theses and Dissertations. 5427.
https://digitalcommons.fiu.edu/etd/5427