performed using actual hindcast waves for the calibration period rather than 

 representative waves such as used in the preliminary modeling. Simulations of 

 projected shoreline response, with and without sand management techniques, 

 were performed as before. Completed results from the comprehensive shoreline 

 response modeling task were not available at the writing of this paper, but 

 they will be given in Gravens , et al . (in preparation). 



BAY RESPONSE NUMERICAL MODELING 



Purpose . The twofold purpose of the bay response modeling task was (1) to 

 estimate the effects of the proposed ocean entrance alternatives on tidal 

 circulation and constituent transport in the Bolsa Bay complex, existing and 

 proposed wetlands, Huntington Harbour complex, and Anaheim Bay, and (2) to 

 qualitatively assess impacts to water quality based on existing data and 

 constituent transport estimates. 



Scope . The scope of work for this task included the following: 



a. Evaluation of available numerical models and selection of the 

 most appropriate model for application to the project. 



b. Gathering of existing and new field measurements necessary for 

 the model study and water quality assessment. 



c. Calibration and verification of the tidal circulation numerical 

 model to existing conditions. 



d. Application of the model to test sponsor -provided concepts for 

 both navigable and non-navigable entrance alternatives. 



e. Assessment of water quality based on existing data and numerical 

 transport simulations. 



Methodology . The most suitable numerical model for application to Bolsa 

 Chica and surrounding tidal regions needed to successfully simulate the flow 

 characteristics of the channelized Anaheim Bay, Huntington Harbour, and Outer 

 Bolsa Bay regions, and to satisfy the requirements of the water quality 

 modeling effort. The selected model was a link/node model with the basic 

 features of: inundation of low-lying terrain, treatment of hydraulic control 

 structures such as culverts and tide gates, and utilization of actual bathym- 

 etry with spatially-varying bottom roughness. The link/node model divides the 



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