US Army Corps of Engineers

Climate Change Adaptation

Comprehensive Evaluation of Projects with Respect to Sea-Level Change (CESL)

The purpose of the Comprehensive Evaluation of Projects with Respect to Sea Level Change (CESL) is to conduct a series of progressively more detailed screening-level assessments of the vulnerability of USACE projects to the effects of changing sea levels. This process will identify projects that require more detailed analyses and those which will require adaptation sooner.

The screening-level assessments were completed by USACE district staff using a web-based tool that interfaces with USACE geospatial databases, reflect USACE sea level change guidance, and incorporate the sea level calculator. Access to this tool is currently limited to USACE only. The comprehensive evaluation with respect to sea level (CESL) web tool also relies on information developed by other agencies, including the Federal Emergency Management Agency (FEMA), National Oceanic and Atmospheric Administration (NOAA) and the US Geological Survey (USGS).This effort relies on the extensive expert science provided by the NOAA National Ocean Service with respect to tides and gauges. Their participation on the USACE team allows rapid infusion of science into engineering.

Coastal areas in the U.S. are economic drivers for the whole country, supporting port commerce, valuable fisheries, and multiple revenue streams for state and local governments. However, coastal areas are especially vulnerable to hazards, now and in the future, posed by waves and surges associated with sea level change and coastal storms. Recent hurricane events have emphasized the increasing vulnerability of coastal areas to natural disasters through the combination of changing climate, geological processes and continued urbanization and economic investment. Compared to sea level change, there is less knowledge and less consensus of opinion about how climate change will impact coastal storms. To add even more complexity, these effects will likely be different in the Atlantic than the Gulf of Mexico, and even more different than for the Pacific Coast.

USACE continues to work with Federal science agencies and other experts to learn more about coastal climate change impacts and how to adapt to these changes that can cause damages to human life and property as well as ecosystems. USACE considers the full array of coastal risk reduction measures, including natural or nature-based features (e.g., dunes), nonstructural interventions (e.g., policies, building codes and land use zoning, and emergency response such as early warning and evacuation plans), and structural interventions (e.g., seawalls or breakwaters), and combinations of these features. Natural and nature-based features can attenuate waves and provide other ecosystem services (e.g. habitat, nesting grounds for fisheries, etc.), however, they also respond dynamically to processes such as storms, both negatively and positively, with temporary or permanent consequences. Nonstructural measures are most often under the jurisdiction of State and local governments (and individuals) to develop, implement and regulate, and cannot be imposed by the federal government. Perhaps more well-known are the structural measures that reduce coastal risks by decreasing shoreline erosion, wave damage and flooding.

Together with its partners and stakeholders, USACE can apply science and engineering to configure an integrated approach to risk reduction through the incorporation of natural and nature-based features in addition to nonstructural and structural measures that also improve social, economic, and ecosystem resilience. To clarify our commitment to using the full array of measures for coastal risk reduction, USACE recently published a report "Coastal Risk Reduction and Resilience: Using the Full Array of Measures."

Sea-Level Change Adaptation

Sea-level change has been the focus of intense interest by the U.S. water resources science agencies (NOAA and USGS), along with other agencies contributing to the U.S. Global Change Research Program (USGCRP, 2009) and the third US National Climate Assessment You are leaving a Federal Government web site. Click this icon for more information. (2014). Among the recent science reports supporting the development of new guidance are the NRC's 2012 report Sea-Level Rise for the Coasts of California, Oregon, and Washington: Past, Present, and Future You are leaving a Federal Government web site. Click this icon for more information. and the expert report published by NOAA-USGS-SERDP-USACE on Global Sea Level Rise Scenarios for the United States National Climate Assessment This link leaves this site for another Federal Government web site., which was written in support of the 2013 National Climate Assessment. Finally, agency reports and peer review literature contain more than 10,000 citations in the area of sea-level change (or sea-level rise).

Because of the importance of coastal areas to the missions and operations of the USACE, the agency has considered sea-level change in its planning activities since 1986, beginning with EC 1105-2-186: Planning Guidance on the Incorporation of Sea Level Rise Possibilities in Feasibility Studies (pdf, 609 KB) in 1989. In 2000, USACE incorporated sea-level change considerations in its Planning Guidance Notebook, and in 2009, released an Engineer Circular (EC) 1165-2-211, Incorporating Sea-Level Change Considerations in Civil Works Programs (pdf, 457 KB), Engineer Circular (EC 1165-2-212 Sea-Level Change Considerations for Civil Works Programs). Engineer Circulars have a two-year lifespan, so this EC has been superseded by Engineer Regulation 1100-2-8162, Incorporating Sea Level Change in Civil Works Program, released in December 2013. In July 2014, USACE published guidance on how to adapt to changing sea levels, Engineer Technical Letter 1100-2-1, Procedures to Evaluate Sea Level Change: Impacts, Responses and Adaptation (pdf, 4.75 MB). An existing probabilistic tool used to assess vulnerability of non-developed natural coastlines or beach protection projects (Beachfx) has been updated for use with the new sea-level guidance.

USACE has a nationwide interagency team that includes external and international experts currently engaged in developing follow-on guidance that will evaluate total water levels affected by surge, waves, and tides in addition to sea level change.

USACE also provides support through its Responses to Climate Change Program to interagency efforts such as the recent USGS effort related to coastal landscape response to sea-level rise assessment for the northeastern United States, which includes a report, website and data tools.


 Screening-Level Assessment of Projects with Respect to Sea Level Change Report



Screening-Level Assessment Report Completed

The U.S. Army Corps of Engineers (USACE) has released Screening-Level Assessment of Projects with Respect to Sea Level Change (pdf, 1.33 MB). The report is the first in a series of progressively more detailed screening assessments and detailed assessments of the most vulnerable projects and those with the highest consequences. The screening level assessments were completed using the Comprehensive Evaluation with Respect to Sea Level (CESL) web tool and relies on information developed by other agencies, including the Federal Emergency Management Agency (FEMA), National Oceanic and Atmospheric Administration (NOAA) and the U.S. Geological Survey (USGS).

The results of this screening level analysis are providing a foundation for USACE to continue a program of progressively more detailed screening assessments before embarking on detailed assessments of the most vulnerable projects and those with the highest consequences. The CESL tool used in USACE screening-level analyses can be made available to others who wish to perform similar coastal vulnerability assessments. This technical transfer has already begun, with the transfer of the technology to Army staff for Installations, Environment, and Energy in 2015. Other users are encouraged to work with the contractors to evaluate the necessary modifications to suit their own particular purposes. By developing, testing, and making this toolkit available to others, USACE is well-aligned with the recommendations of the White House State, Local, and Tribal Leaders Task Force released in November 2014.

Comprehensive Evaluation of Projects with Respect to Sea-Level Change Fact Sheet


Initial Vulnerability Analysis Completed

The first phase of the CESL is the Initial Vulnerability Assessment (IVA). The IVA used the CESL tool to determine the impact of sea level change at the 50- and 100-year planning horizons for coastal projects included in the Corps Project Notebook and located within 40 miles of NOAA's tidally influenced water bodies.

The IVA was completed by district teams overseen by the CESL project team in September 2014. Approximately 1500 projects were identified for IVA. Of these, about 1/3 of the projects were considered to be impacted by sea level change, requiring more detailed assessment. Based on the scores of these potentially impacted projects, about 1/4 were classified as potentially having high or very high impacts. At the current time, the results are undergoing quality assurance and quality control checks. Prioritization of potentially impacted projects begins in early FY15 for the next phase of CESL, with projects classified by IVA as very high or highly vulnerable receiving priority for examination in more detail. A fact sheet (pdf, 292 KB) on the IVA is attached, and a full report is expected to be released in December 2014.