While October 2012's Superstorm Sandy dealt its most powerful blow to the Eastern Seaboard from Maine to Virginia, it also affected regions as far south as Florida and as far inland as the Great Lakes region, according to a new study from the U.S. Army Corps of Engineers (USACE). But risk-reduction measures completed before the storm at several of the Corps' coastal projects helped to mitigate damage at those locations, the study finds.

Photo By Dan Desmet/USACE New York District

Fact-Finding Mission: In the days following Superstorm Sandy, Corps workers assess the impact of the storm on a beach at Avon-by-the-Sea, N.J.

"It appears that the overall damage from the storm would have been much more severe if these projects had not been in place," the Corps says in a Dec. 19 statement.

However, the storm, which exceeded 500-year storm levels in some areas, "overtopped" even several of these projects, says the Corps, which conducted the study as directed in the federal Disaster Relief Appropriations Act of 2013.

The Hurricane Sandy Coastal Projects Performance Evaluation Study evaluated 75 constructed coastal storm risk-management projects in USACE's North Atlantic Division; 31 projects in its Great Lakes and Ohio River Division; and nine in its South Atlantic Division. The study's purpose was to determine these projects' effectiveness in both engineering and economic benefits as well as in their ability to reduce the overall risk to coastal communities.

The study, which can be downloaded at the corps' Web site, www.nan.usace.army.mil/SandyPPE, includes recommendations for potential improvements as to how these types of projects are formulated. These include determining how to address the impacts of back-bay flooding of barrier islands; and evaluating the efficacy of natural and engineered dunes in reducing damage. Some projects with either high storm berms or with berms backed by significant dunes generally performed better than projects involving a berm alone, the study finds.