The objective of this task is to develop site specific deepwater wave climates all around the Lake Michigan shoreline for each of the alternate water level scenarios being developed by GLERL. This information is required as input for the hydrodynamic, coastal process and flood inundation modeling activities. The WIS hindcast deepwater wave database completed by the USACE Waterways Experiment Station covers the period from 1956 to 1987 for the entire lake. An additional period of coverage (1991 to 1993) was completed for the St. Joseph Harbor MCCP project. Additional modeling was conducted to develop a complete database from 1956 to 1997. This data was transferred to a nearshore depth of 8 to 10 meters at all of the Study Sites. Baird & Associates have also completed site specific one-dimensional hindcasts to fill gaps in the spatial coverage of the WIS stations. This resulted in the production of a series of wave roses for each station (see Figure below for an example).

Baird have also incorporated the influence of ice conditions on the wave predictions as part of the Flood and Erosion Prediction System, and particularly the issue of shore ice protecting the nearshore and backshore zones. To do this, ice cover maps were input into the system and allowances in the wave climate calculations were made for those periods when ice of significant thickness and accumulation was along the shoreline.

In FY99, a comparison of historic monthly wave energy to average monthly lake levels was conducted at representative locations around the lake (including bays) to determine most likely wave conditions for each of the alternate hydrologic scenarios (see Figure below). This analysis found that on the west side of the lake in particular there was a definite correlation between periods of rising lake level and rising wave energy. In cases where no significant correlation between lake levels and wave energy could be found at some or all of the locations around the lake, random selection of monthly or yearly wave conditions was used to build a possible future wave climate for each of the water level scenarios. Wave climate scenarios have now been developed for the various water level scenarios based on these findings.

For the five prototype counties, the deepwater wave climate data will be added to storm surge/drawdown hourly values. Then, a random generation of monthly mean stillwater values for each scenario will be added to the wave & surge/drawdown data to generate a set of 50 years of data to use in the FEPS model. This task was completed for the five prototype counties in 2000. WES will continue to develop WIS data for the remaining Lake Michigan counties in 2001 and 2002.

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