Mudflats, also known as tidal flats, are unvegetated areas consisting of mud, sand and/or gravel, and are regularly exposed and flooded by the tides. They exist in sheltered areas with low wave-action, inlets and estuaries, and are formed by the deposition of fine sediments that have been suspended in the sea or estuary.

Mudflats provide important habitat for bottom-dwelling invertebrates, such as clams and mussels, and thus provide food for predatory fish, birds and invertebrates such as the horseshoe crab, mudsnail and shellfish species.

Changes in water patterns from development may increase or decrease water flow. Contaminants, such as heavy metals, hydrocarbons, wastewater, and stormwater, can add to water quality degradation.

For more information contact the New Hampshire Coastal Program at (603) 431-9366 or visit www.des.nh.gov/coastal.