Aside from its own concerns, MDE has received input from the Maryland Department of Natural Resources, the U.S. Environmental Protection Agency, the National Marine Fisheries Service, and the U.S. Fish & Wildlife Service identifying the many ways that these types of projects can negatively affect the health and vitality of Maryland’s coastal wetland resources. For example, pier structures can cut off sunlight to a long swath of tidal marsh, killing the vegetation that lies beneath. This loss of vegetation represents a loss of wetland habitat and accelerates the erosion of the marsh that is naturally kept in place by the vegetation’s root structure. Bringing boat traffic in close proximity to the marsh further accelerates this erosion.

Construction of long piers also results in fragmentation of marsh ecosystem by erecting barriers to the movement of resident species throughout the marsh. For example, many wading birds need shallow waters and often prefer guts within marsh that offer protection from predators. Densely spaced piers hinder a bird’s escape route from a site and therefore discourage usage by some species. These same barriers, and the de-vegetated areas beneath piers, allow for the entry of non-native species to the marsh, further disrupting the natural balance of the coastal marsh ecosystem.

Finally, the use of treated lumber in the construction of piers and pilings can introduce contaminants into the marsh environment as the chemicals used to treat the lumber leach out over time. As a steward of Maryland’s wetland resources, MDE has an obligation to consider fully these concerns and has carefully evaluated the biological and scientific research addressing these types of impacts.

While the department was undertaking its analysis, the research assistance branch of the National Oceanic and Atmospheric Administration began its own analysis of these same impacts, culminating in a nationwide workshop of scientists, researchers, and managers to discuss existing research and policy relative to the construction of long piers over wetlands. Two workshops have been conducted and work on these issues continues. The preliminary conclusions of the workgroup show that existing scientific research supports the concerns raised by natural resource agencies.

The State of Maryland is continuing its ongoing efforts with the NOAA Workgroup and is also pursuing additional research. These research efforts, while long term in nature, will provide the necessary scientific data to make sound policy decisions on the construction of piers over marshes. For more information on docks and piers and the next steps that are being considered, go to www.mdcoastalbays.org.

The Worcester County Commissioners will examine whether to limit pier lengths on Jan. 6 at their regularly scheduled meeting.