US Army Corps of Engineers
Baltimore District Website

Stakeholder Update - Feb. 10, 2020

Baltimore Coastal Storm Risk Management Study Stakeholders,

We wanted to touch base with you on the progress of our study to evaluate coastal storm risk and vulnerability within the Baltimore Coastal study area, focusing on regionally critical infrastructure, including port terminals, highways (and evacuation routes), hospitals, public utilities and local airport authority facilities that are susceptible to coastal flooding.

We have an approved Project Management Plan, which guides the study milestones and funding allocations between the Army Corps and the project sponsor, Maryland Department of Transportation.

We are wrapping up the "scoping phase" of our study, which consisted of gathering information, identification of problems and opportunities, preliminary formulation of flood risk management alternatives, and the public meeting/open house, which was held on Sept. 23, 2019, in Baltimore.

We have completed coastal flood inundation mapping within the study area to identify flooding issues and hotspots for "without project" conditions, which means the current and future state of flooding if no projects were to be constructed.  Inundation mapping was performed under different storm scenarios (100 and 500-year floods) and sea level rise projections (Corps of Engineers' "Low", "Intermediate" and "High" projections) for years 2030 to 2080. We have also performed an initial run of our economic model to assess preliminary monetary flood damages in the study area "without project" conditions.

We are currently working on refining the various flood risk management alternatives developed to date based primarily on a rough cost to construct / benefit of construction (flood damages reduced, etc.) analysis.

In compliance with the National Environmental Policy Act, we have sent agency coordination letters to support development of an Environmental Impact Statement that will evaluate potential environmental and cultural resource impacts related to implementation of coastal storm risk management projects. 

We plan to publish a draft Feasibility Report/Environmental Impact Statement for public review around October 2020 that will include our modeling findings, as well as recommendation(s) for a potential coastal storm risk management project.

- Study Team, U.S. Army Corps of Engineers, Baltimore District; Maryland Department of Transportation

Baltimore Coastal Storm Risk Management Study

The objective of this study is to investigate coastal flooding problems, needs and potential solutions for key locations in the Baltimore coastal study area. 

The Baltimore Coastal Study is a 3-year, $3 million study cost-shared evenly between the U.S. Army Corps of Engineers, Baltimore District, and the Maryland Department of Transportation, which is the non-federal sponsor. A federal cost-sharing agreement was signed in August 2019 between the agencies. 

The effort is a spin-off study of the two-year North Atlantic Coast Comprehensive Study (NACCS) that was completed in January 2015 and was commissioned by Congress as part of Hurricane Sandy recovery. The purpose of NACCS was to help local communities better understand their changing flood risks due to climate change and provide them tools to be better prepared for the future. The Baltimore metropolitan region was one of nine high-risk areas identified in NACCS as needing further analysis.  

The goal is to reduce coastal flood risk at key locations to people, properties, infrastructure and resources in the study area, considering future climate and sea level change scenarios. The authority only includes coastal flood risk, not flood risk from heavy, localized rainfall or nuisance flooding. The team will focus on regionally critical infrastructure, including port terminals, highways (and evacuation routes), hospitals, public utilities and local airport authority facilities that are susceptible to flooding. Options to reduce flood risk could include levees, storm surge barriers, flood proofing facilities and living shorelines.

Baltimore Coastal Study Area

The study area is characterized by flat and low-lying elevations. Streams and rivers in the study area all drain into the Chesapeake Bay. The Army Corps and MDOT will work together to select focus areas. 

Baltimore Metro Storm Risk

The Baltimore metro region is highly susceptible to flooding, and future storms may result in increased flood risk, economic damages and life safety concerns, not just for tropical storms and hurricanes but also for nor'easters.

Presidential declarations for seven flood-related disasters were made for Baltimore County between 1971 and 2011. In Baltimore City, alone, annualized damages due to coastal flooding are estimated at $2.2 million.

Hurricane Sandy caused a relatively moderate storm surge in the Baltimore metropolitan region. Historical storms including Hurricane Isabel in 2003 caused more damages in the Baltimore region (7-plus feet at the National Oceanic and Atmospheric Administration's Baltimore gauge station). Heavy rains that occurred several days after Isabel added to localized and flash flooding in the area. Baltimore’s Inner Harbor and Fells Point Historic District along with other waterfront neighborhoods were flooded with up to 8 feet of water.

Through NACCS, sea level change analyses for NOAA’s Baltimore gauge station estimates an increase in mean sea level by the year 2100 of 1.0, 2.1, and 5.4 feet (NAVD) for the low, intermediate and high scenarios, respectively. Coupled with sea level change over time, future storms affecting the Baltimore metropolitan region may result in increased flood risk. Steady population growth and continuing near-shore development is increasing the risk of human injury and property loss.

Study Objectives

The study team will use existing information, models and leverage past studies to help inform this study and expedite the timeline. 

The study team will: 

  1. Assess the study area’s problems, opportunities and what the future conditions would be without a project (incorporating climate and sea level change data);
  2. Assess the feasibility of implementing system-wide coastal storm risk management solutions; and
  3. Assess the feasibility of implementing site-specific structural, non-structural and nature-based flood risk management options. 
  4. Provide recommendations to MDOT, including preliminary designs and cost information. 

Contact

If you have any information related to flooding or flood risk management that may be relevant to this study, including reports, photos or other digital data, as well as climate change impact analyses or studies, please share this information with the study team by sending an email to Cenab-CC@usace.army.mil.