Soft Shoreline Engineering
Soft shoreline engineering is achieved by using vegetation and other materials to improve the land-water interface. This webpage contains links to 51 case studies of soft shoreline engineering along the Detroit River and western Lake Erie, and provides guidance for furthering the use of this important tool.
The lower Detroit River and western Lake Erie are located in the heart of the Great Lakes basin and form an important linkage between the upper Great Lakes and lower Great Lakes. This watershed has nearly seven million residents and substantial industry. As a result of this ample urban and industrial development there has been considerable loss and degradation of habitat. For example, the Detroit River has lost 97% of its coastal wetlands to development and 49.9 of the 51.5 km of U.S. shoreline have been hardened with concrete and/or steel, leaving only 1.6 km of natural shoreline . Despite the enormity of habitat losses, this ecological corridor continues to support a great diversity of wildlife. Because of the history of human settlement, the substantial human population density, and biodiversity of this area, Canada and the U.S. share a long history of cooperative conservation. Out of this international cooperation, the 76.8 km of shoreline along the lower Detroit River and western Lake Erie have been designated North America’s only international wildlife refuge – the Detroit River International Wildlife Refuge. The river and lake are at the intersection of two major North American bird migration flyways – the Atlantic and Mississippi. In addition, the area continues to be a significant fish migration corridor. The Detroit River and western Lake Erie have been recognized for their biodiversity in the North American Waterfowl Management Plan, the United Nations Convention on Biological Diversity, the Western Hemispheric Shorebird Reserve Network, and the Biodiversity Investment Area Program of Environment Canada and U.S. Environmental Protection Agency.
Soft vs. Hard Shoreline Engineering
Hard Shoreline Engineering:
Hard shoreline engineering is generally defined as the use of concrete breakwalls or steel sheet piling to: stabilize shorelines for protection from flooding and erosion; achieve greater human safety; and/or accommodate commercial navigation or industry. Although hard shoreline engineering can achieve commercial, navigational, and industrial benefits, it typically results in negative ecological impacts because it provides no habitat and restricts access to adjacent habitats. Such anthropogenic hardening of shorelines not only destroys or degrades natural features and biological communities, but it also alters the transport of sediment, disrupting the balance of accretion and erosion of materials carried along the shoreline by wave action and long-shore currents. This disruption of sediment transport processes can intensify the effects of erosion, causing ecological and economic impacts.
Soft Shoreline Engineering:
Today, there is growing interest in developing shorelines for multiple purposes so that additional benefits can be accrued. Soft shoreline engineering is the use of ecological principles and practices to reduce erosion and achieve stabilization and safety of shorelines, while enhancing riparian habitat, improving aesthetics and even saving money. Soft shoreline engineering is achieved by using vegetation and other materials to improve the land-water interface, thereby improving ecological features without compromising the engineered integrity of the shoreline.
The 38 soft shoreline engineering projects reported on here were undertaken for a variety of reasons and employed a number of different approaches or management tools to enhance/improve riparian or aquatic habitat. All provide “teachable moments” for the value and benefits of habitat enhancement and restoration. However, the value of such projects, both from an ecological and an economic point of view, could be improved by addressing the following key lessons learned:
- Involve habitat experts up front in the design phase of waterfront planning.
- Establish broad-based objectives for shoreline engineering with quantitative targets for project success.
- Ensure sound multidisciplinary technical support throughout the project (e.g., the Natural Resources Conservation Service’s Soil Bioengineering Team).
- Start with demonstration projects and attract many partners to leverage resources.
- Treat habitat modification projects as experiments that promote learning, where hypotheses are developed and tested using scientific rigor.
- Involve citizen scientists, volunteers, university students, and/or researchers in monitoring, and obtain commitments for post-project monitoring of effectiveness up front in project planning.
- Measure benefits and communicate successes.
- Promote education and outreach, including public events that showcase results and communicate benefits.
State of the Straight 2010 Report - Ecological Benefits of Habitat Modification - [download PDF]
Land and Water Management Article - Ecological Benefits of Habitat Modification - [download PDF]
Ecological Engineering Article - Soft shoreline engineering survey of ecological effectiveness - [download PDF]
For more information, contact John Hartig (John_Hartig@fws.gov) or Anna Cook (Anna_Cook@fws.gov), U.S. Fish and Wildlife Service