Racine County initiated a monitoring program for Racine Harbor, as the original north and south breakwaters were constructed over 100 years ago. The typical design useful life for Great Lakes coastal structures is 25 to 50 years, given that annual maintenance is provided. The harbor structures are subject to annual significant waves, typically over 10 feet during storms with a long fetch over Lake Michigan, especially from the northeast. Significant deterioration of the coastal structures subject to significant wave and ice conditions has been observed with time. Periodic maintenance monitoring work is required to proactively identify the need for short and long-term repairs and plan for funding, given the considerable cost of the marine repairs.
Dan Veriotti was the project manager and lead engineer in 2017 for a comprehensive above-the-water evaluation of the existing conditions for the north and south breakwaters, coupled with an underwater investigation of the north breakwater. GZA is now conducting a new assessment in 2022. The data collection included aerial, topographic and bathymetric surveys. A site investigation detailed the existing conditions through detailed photographs at reference stations, visual inspection and measurements. A computer volumetric analysis was performed for the new built surfaces to quantify areas of sediment scour (deepening) and shoaling (deposition); historic and new cross-sections were developed and compared to identify any changes. The aerial survey identified individual armor stone displacements. Repair priorities were formulated with construction cost estimates. Conceptual engineering plans for the north breakwater were submitted for regulatory permitting and FEMA grant application.
The project team led by Dan Veriotti, PE has great knowledge of the Harbor areas and adds great value to the project and facilitates the successful long-term management of these structures. The proactive approach to monitor the conditions will likely eliminate a reactive (after a significant storm) approach to implement repairs for a significantly higher cost. GZA is now under contract for evaluation of concrete repairs for the North Breakwater and assistance with grant funding.