County presents 2025 high-tide flood mitigation update, urges better modeling and community reporting

Calvert County staff presented an update to the county's high-tide flood mitigation plan required by state law, outlining risks, vulnerabilities and mitigation opportunities for waterfront communities.

"This plan evaluates the risks, vulnerabilities, and mitigation opportunities facing Calvert County given nuisance flooding or high tide flooding," said Molly Fleetham, environmental planner. Fleetham noted staff secured a state grant to help fund the update and said the plan focuses on three priorities: evaluating risks and vulnerabilities, identifying the most-impacted areas within the county, and offering mitigation solutions. She gave regional context, noting a recent local trend in sea-level rise: "In 2019, the sea level rise rate was 3.88 millimeters a year. Now, it's 4.11 millimeters per year." The presentation also reported that incidences of high-tide flooding in 2024 were "more than double the frequency of any year prior going back to 1980."

Staff emphasized vulnerabilities for critical infrastructure, community resources, aquaculture and agriculture, and natural resources such as marshes and aquifers. Recommended steps included expanding modeling to better identify affected buildings, deploying sensors to track water levels, encouraging residents to report flooding via the MyCoast app, studying frequently flooded roadways and seeking partnerships for nature-based solutions such as shoreline and marsh restoration projects. Commissioners asked whether staff planned to produce community-level mitigation plans; Fleetham said improved modeling is the first step and community-specific plans may follow as resources allow.