Delaware — Delaware environmental officials have released new data predicting where tidal wetlands are most likely to migrate as sea levels rise along the state’s coastline. The Department of Natural Resources and Environmental Control updated its 2017 Marsh Migration Model in 2023 using elevation-based geographic data and sea level rise projections to determine which areas could support future tidal wetlands. The modeling identified 21,449 acres across the state as highly suitable under a 4-foot sea level rise scenario. Sussex County had the most suitable acreage at 9,418, followed by Kent County with 8,482 acres, and New Castle County with 3,549.
DNREC’s study revealed that nearly 70% of suitable areas are either non-tidal wetlands or agricultural lands, with most of that land in private ownership. The updated model used a 0 to 12 rating scale to score suitability based on factors such as elevation, distance to existing wetlands, and land use. DNREC officials say the data will support long-term conservation planning, public land management, and stakeholder engagement. It will also help landowners and planners identify where wetlands are likely to move as their current locations are gradually submerged. Study findings and a summary flyer are available through DNREC’s online platform and at de.gov/marshmigration.
