FHWA Green Infrastructure Techniques for Coastal Highway Resilience Project
In spring 2016, the Federal Highway Administration launched the "Green Infrastructure Techniques for Coastal Highway Resilience" project to explore innovative ways that transportation agencies can use green infrastructure or nature-based solutions to make highways more resilient to coastal hazards, including storm surges and sea-level rise. Through the program, FHWA funded five pilot projects across different coastal states to evaluate different green infrastructure approaches and develop lessons-learned. FHWA considers "coastal green infrastructure" to include dunes, wetlands, living shorelines, oyster reefs, beaches, and artificial reefs.
The five funded pilot projects are evaluating different types of coastal green infrastructure for their effectiveness at reducing risk to coastal roadways and bridges:
- The Delaware Department of Transportation is developing conceptual designs for nature-based solutions, including living shorelines, for five sites along a state highway between Rehoboth Beach and Fenwick Island.
- The Maine and New Hampshire Departments of Transportation are partnering to study future sea-level rise and storm surge impacts on portions of state coastal highways and to develop green infrastructure solutions that address vulnerabilities.
- The Mississippi Department of Transportation, in partnership with the University of South Alabama, is evaluating the potential for a vegetated berm to protect bridge approach spans that were reconstructed after Hurricane Katrina.
- The Oregon Department of Transportation is exploring the use of cobble beaches to protect portions of Highway 101 along the Pacific coast.
- The US Army Corps of Engineers is studying the use of living shoreline and marshes for protecting a roadway in New Jersey, including exploring the effectiveness of wetlands at buffering against high tide or storm events and ascertaining any minimum width of marshes needed to protect roads.
The recipients of pilot project funds will produce reports documenting the conceptual designs developed for the nature-based solutions evaluated, an assessment of infrastructure protection and environmental benefits that would be derived from the solution(s), any permitting requirements, and initial construction and long-term maintenance costs, as well as other challenges and solutions encountered. Reports are anticipated to be published in late 2017.
In addition to funding the five pilot projects, the Green Infrastructure Techniques for Coastal Highway Resilience Project will produce a white paper on the current state of practice around green infrastructure and coastal resilience for highways. FHWA is hosting regional peer exchanges to solicit more input from transportation agencies and stakeholders, and will also develop an implementation guide for transportation professionals to assist with decisionmaking related to the use of green infrastructure in coastal highway environments. The entire project is being funded using a portion of FHWA's annual Strategic Initiatives research budget.
Publication Date: 2016 - 2017
- Best practice