Modeled impacts of channel dredging on storm surge produced by Category 4 hurricanes in Corpus Christi Bay, Texas - Storm 319

The Port of Corpus Christi Authority (PCCA) has started to deepen the Corpus Christi Ship Channel (CCSC) to a depth of -54 feet (MLLW) from the existing depth of -47 ft (MLLW) as well as widening it in select reaches. PCCA is also planning to deepen the outer reach of the ship channel (from the Gulf of Mexico to the ferry landing at Harbor Island) from the currently authorized depth of -54 ft (MLLW) to approximately -75 ft (MLLW) within the footprint of the -54 ft channel. The -54 ft channel will have -2 ft advance maintenance and -2 ft allowable overdepth, resulting in a total depth of -58 ft. Similarly, La Quinta Channel (LQC) will have a depth of -47 ft with -2 ft advance maintenance and -2 ft allowable overdepth, resulting in a total depth of -51 ft (MLLW). These ship channel improvements would allow larger ships access to the port that will generate a positive return on investment by reducing delays and congestion and increasing the efficiency and safety of port operations.

This study assesses the impacts of the ongoing and proposed channel improvement projects on storm surge water levels and inundation duration patterns in the Corpus Christi Bay system by creating and applying site-specific hydrodynamic models. The coupled hydrodynamic storm surge model Advanced CIRCulation (ADCIRC) and Simulating Waves in the Nearshore (SWAN), is used to simulate bay hydrodynamics with existing channel configurations and compared to new simulations where the channel configurations are altered in the model. Three channel configuration scenarios are used: (1) Existing Scenario (ES) representing the existing channel conditions with depth of -47 ft (MLLW); (2) Ongoing Project Scenario (OPS) representing the currently ongoing channel improvement project scenario with depth of -54 ft (MLLW) plus -4 ft for advance maintenance and allowable overdepth; and (3) Future Project Scenario (FPS) representing the proposed future channel deepening project with depth of -75 ft (MLLW) at the outer reach of CCSC from the Gulf of Mexico to Harbor Island. The hydrodynamic storm surge modeling is conducted with two synthetic Category 4 storms (Storm 319 and Storm 414) under three channel configuration scenarios (ES, OPS and FPS). The model is run in the HPC resources in the Texas Advanced Computing Center (TACC) at University of Texas at Austin.

This data package contains input meshes representing three channel configurations, model parameter and setup file and modeling outputs of each channel configurations with synthetic Cat 4 Storm 319 showing water surface elevation time series in the model grid (fort.63), velocity time series in the model grid (fort.64), and maximum storm surge elevation at each node during a storm event (maxele.63). Storm 319 is a slower-moving storm than 414, with a smaller wind field and higher wind speeds, and makes landfall on North Padre Island near Bob Hall Pier. Modeling results for Storm 414 are available in related dataset HI.x833.000:0008 (doi: 10.7266/PEB15Y1N).