June 27, 2020
By Kayla Wandsnider, Coastal Resilience Project Assistant, Wisconsin Sea Grant
This project was funded as part of the Southeastern Wisconsin Coastal Resilience project led by the Wisconsin Coastal Management Program. To be eligible for this funding and guide project development, Lake Michigan coastal local governments completed a Coastal Resilience Self-Assessment (link) to help prioritize top coastal hazard concerns and identify potential actions to enhance their capacity to plan, prepare for and adapt to coastal hazards. Funding for this project was provided by the National Atmospheric and Oceanic Administration (NOAA) Coastal Resilience Grants Program, Grant # NA17NOS4730144.
Kemper Center Shoreline Protection Design Case Study
Title of Project: Kemper Center Shoreline Protection Phase III
Organization applying: Kenosha County Division of Parks
Total project cost: $61,480
Grant award: $30,000
A PDF of this case study with more details is available here: Full Kenosha County Shore Protection Case Study PDF.
- Kenosha County Division of Parks
- Kenosha County Emergency Management Department
- The City of Kenosha
- Kemper Center, Inc
- Consultant Engineering Firms
- United States Army Corps of Engineers
- Wisconsin Department of Natural Resources
The Coastal Resilience Issue
The grounds of the Kemper Center, a cultural and recreational facility which is the only Lake Michigan coastal property owned by Kenosha County, has been routinely damaged by a combination of coastal storms and high Lake Michigan water levels. The shoreline of the Kemper Center currently consists of a degraded stone revetment that no longer provides an adequate level of protection from the combination of coastal storms and lake level fluctuations that are routine on this stretch of Lake Michigan. With every large storm, the revetment continues to degrade through the displacement of armor stone and subsequent lowering of the crest elevation. This leaves the Kemper Center and its grounds increasingly vulnerable to coastal erosion and flooding. The January 2020 storm caused enough damage across Kenosha, Racine and Milwaukee Counties to qualify for a FEMA Major Disaster Declaration (DR-4477).
Kenosha County’s completed Coastal Resilience Self-Assessment highlighted priority needs to rehabilitate shoreline protection structures that protect coastal assets and ensure that shore protection structures are routinely inspected and maintained to ensure long-term function. These needs aligned well with the redesign of the revetment at the Kemper Center.
Vision for the Community
Kenosha County wants to protect the shoreline at the Kemper Center from ongoing erosion and flooding damage so that the grounds can continue to serve as a community gathering space, recreation area and shared-use thoroughfare along Lake Michigan.
There is a need to develop sustainable strategies to adequately protect the shoreline that still maintains public access to the Kemper Center shoreline.
The main strategies include:
- Rehabilitate the degraded shoreline revetment
- Extend or relocate stormwater outfalls
- Regrade the site to preserve the use of activity spaces in the park
What was accomplished
Kenosha County used a phased approach for making design progress while leveraging their funding. They started working on designs and specifications for a shoreline protection project in 2017. Kenosha County worked with engineering consultants to complete this work in multiple phases to determine the best design as informed by site investigations and studies while also leveraging available funding opportunities.
Phase I started with a coastal engineering study to develop conceptual strategies in order to improve public access to the Kemper Center shoreline.
Phase II began the coastal engineering design of the preferred shore protection alternative: a revetment and cobble beach for public access. The revetment was designed following U.S. Army Corps of Engineers Great Lakes design practices to withstand a combination of 20-year return period water levels and storm surge (i.e. a 5% chance of occurring in a year) and 10-year return period wave conditions (i.e. a 10% chance of occurring in a year).
Phase III is the current project which focuses on three goals:
Goal 1 – Design a Stormwater Management and Site Grading Plan
A consultant engineering firm completed storm sewer and site grading designs to improved drainage, relocate discharge away from the proposed cobble beach and reduce outfall damage by waves, debris and ice.
Goal 2 – Site Investigations
Site investigations analyzed and cataloged the entire shoreline and existing revetment materials to determine the quantity of material such as granite armor stone that could be salvaged for reuse in the final shore protection design.
Goal 3 – Regulatory Coordination
One of the most important goals of this project was to further the regulatory coordination for the project. By coordinating early with regulatory agencies, any issues with the designs will hopefully be resolved early in the process.
Partnerships Reinforced or Made
After the January 2020 storm damage, Kenosha County Parks met with coastal engineers, Wisconsin state officials, and FEMA representatives on site of the Kemper Center shoreline to show and assess damage left in wake of the January winter storm event.
With the shoreline protection and site designs in-hand, Kenosha County will seek support for long-term sustainable management and repairs of the Kemper Center shoreline that will reduce the impact of damage in the strong storms and high lake levels inevitably occur again.
- Using a phased approach helped move the project forward by keeping it manageable and allowed various funding opportunities to be leveraged as they arose.
- Addressing stormwater management concurrent with the shore protection design allowed for the two systems to work better together to reduce flooding and damage to the stormwater infrastructure.
- When the January 2020 coastal storm struck, the site surveys, inventories, and investigation results helped to quickly quantify the damage.
- The preparation of design documents for construction of the shoreline rehabilitation positions the project to be shovel-ready for seeking implementation funding.