Natural features to play crucial role in building a more resilient Great Lakes coastline

Communities along the Great Lakes coastline are experiencing increased frequency in coastal flooding and erosion, causing property damage, putting lives at risk, and disrupting local economies.

Recent historic high lake levels illustrate the widespread vulnerabilities along the coast.

With the support of the Engineering With Nature® (EWN) program, the U.S. Army Corps of Engineers (USACE) and the U.S. Army Engineer Research and Development Center (ERDC) can provide technical direction and guidance to USACE Districts around the nation to look at innovative ways of improving coastal resilience.

Using natural and nature-based features (NNBF), which are measures and techniques that can be incorporated into shore protection, improved coastal resilience can be achieved while producing additional economic, environmental and social benefits.

NNBF integrates naturally with the concept of Multiple Lines of Defense (MLD), whereby multiple strategies are used to erect a system of comprehensive, resilient and sustainable coastal storm risk management solutions.

However, current understanding of NNBF and MLD coastal resiliency measures is mostly limited to the ocean coast, resulting in lack of confidence on the applicability and cost-effectiveness of these measures within the Great Lakes. Multiple engagements and discussions across the Great Lakes with communities and stakeholders revealed the need for NNBF and MLD guidance specific to the Great Lakes.

Without greater understanding and guidance, a paradigm shift from traditional structural and non-structural coastal storm risk management practices to more innovative NNBF and MLD measures will not occur. 

USACE also needs this guidance to confidently consider these types of measure as part of the recently initiated Great Lakes Coastal Resiliency Study (GLCRS) and related spin-off studies. Through GLCRS, USACE has the unique opportunity to directly apply this guidance in planning for coastal resiliency at a watershed scale. 

There are 5,200 miles of U.S. coastline across the five Great Lakes and connecting channels, more than double the coastline along the U.S. Atlantic Ocean, and more than three times the coastline on the U.S. West Coast, further underlining the need for Great Lakes specific NNBF and MLD guidance.

Objective

The objective of this effort is to develop a Great Lakes-specific guide – or playbook – to natural and nature-based features (NNBF) and Multiple Lines of Defense (MLD) to improve future coastal resiliency.

The guide will significantly advance the understanding of NNBF and MLD innovative technologies as applied to the entire Great Lakes region. It will also provide additional confidence to federal, state and local government agencies to plan, design, and implement sustainable, adaptable and cost-effective NNBF measures, either instead of, or in addition to, traditional structural and non-structural flood risk management (FRM) practices.

“We are excited to be supporting the Great Lakes with development of the EWN Playbook,” Dr. Jeff King, EWN’s National Lead and Program Manager. “Information and NNBF designs offered in the playbook will help communities and stakeholders better understand the multi-purpose benefits and opportunities that can be achieved when NNBFs are integrated into the landscape to improve coastal resiliency.”

Approach

This effort uses a three-pronged approach to developing the guidance, consisting of:

• Working with partners to identify existing NNBF and MLD projects to assess and quantify their performance and cost under a range of conditions in the Great Lakes.
• Utilize EWN principles to develop new conceptual designs specific to the Great Lakes that achieve greater resiliency and adaptability than conventional FRM designs.
• Estimate adaptive capacity, failure tipping points, and planning level cost/benefit performance outputs of innovative conceptual NNBF and MLD designs under a range of current conditions and future climate scenarios.

Outcomes

This playbook will include broad strategies and examples of projects to advance NNBF and MLD measures, considering stakeholder preferences, as well as the unique challenges and opportunities across the Great Lakes region.

Local, regional and state agencies will gain a better understanding of the NNBF and MLD opportunities, benefits and performance on the Great Lakes that they can consider in their coastal resiliency efforts.

Additionally, the GLCRS will be able to immediately action the Great Lakes EWN Playbook by considering identified NNBF and MLD measures in the coastal resiliency planning.

This effort will enable innovative coastal resiliency solutions to be planned, designed and implemented across Great Lakes into the future, resulting in greater economic benefits (less disruption to local economic activities), environmental benefits (restoration of Great Lakes coastal ecosystems) and social benefits (less loss to recreational amenities and personal property).