Tidal wetlands, commonly referred to as marshes, occur along the shoreline where oceans, bays, rivers, and streams meet the land. They can range from freshwater to saltwater and have water pushed in and out daily by tidal cycles. These wetlands are assessed through watershed report cards and may also be regulated by the state. You will need to apply for permit(s) if you want to install a dock, stabilize your shoreline, build a house, or complete most activities in a tidal wetland.
There are two types of tidal wetlands in Delaware: saltmarshes and freshwater tidal marshes.
Saltmarshes, also known as estuarine wetlands, cover Delaware's coast from the upper edges of the Delaware Bay near the C&D Canal to the Inland Bays in the south near the Maryland border. These habitats are flooded twice daily and are strongly influenced by saltwater carried in from the ocean and bay. Spartina sp. grasses characterize the tree-less landscape in the higher-salinity wetlands closer to the Bay, while a greater variety of plants can be found in areas with less salt further north.
Why are saltmarshes important?
Saltmarshes provide critical nursery habitat for fish and shellfish, vital resting areas for migratory waterfowl and wading birds, and protect us from impacts of coastal storms and floods. Currently, many are being lost to sea level rise and erosion. One way to allow saltmarshes to persist and protect us into the future is to let them move inland through a process called marsh migration.
Freshwater Tidal Marsh
Like salt and brackish marshes, freshwater tidal wetlands are flooded daily with tidal inputs, but are so diluted by freshwater sources that their salinity levels are close to zero. These conditions allow for a wide diversity of wetland plants, including spatterdock, pickerelweed, arrowhead, cattail, wild rice, water-willow, buttonbush, and others. Freshwater tidal marshes are becoming rare in Delaware due to saltwater intrusion from sea level rise. The best remaining examples occur upstate along the Christina River and downstate along the upper reaches of the Nanticoke River.
Page reviewed 4/4/19