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The Great Marsh Region, extending from the Essex Bay Estuary north to Hampton Harbor in New Hampshire , forms the largest continuous stretch of salt marsh in New England at 17,000 acres. A considerable acreage of salt marsh has been lost along U.S. coastlines, but the Great Marsh Region includes some of the most extensive and healthiest salt marshes remaining in the Northeast. The marshes provide tremendous ecological benefits, as well as economic, social, and cultural values to the region. Coastal wetlands within the region have been subjected to a number of direct and indirect impacts from past and current land use practices. While the Great Marsh Region remains relatively intact, aquatic and estuarine portions of the ecosystem are in decline due to a variety of human stressors.

What are Salt Marshes?
Salt marshes are the predominant type of coastal wetland in the Great Marsh and are integral components of estuarine ecosystems. They are areas of transition in the coastal, intertidal zone, recognized by their unique, salt tolerant vegetation. Salt marshes are dependent on precisely coordinated cycles of tides, sediment deposition, and erosion. As a result, the Great Marsh is a highly productive ecosystem that offers habitat for a wide variety of plants and animals, including migratory birds and anadromous fish. The Great Marsh has also played an important historical socio-economic role in the region, and continues to provide tremendous values and services to local communities and the larger Gulf of Maine region.

Conditions in the Great Marsh
Salt marshes within the Great Marsh Region, as in many areas, have been subjected to numerous human stressors, including filling, dredging, extensive ditching, water quality impacts, loss of upland buffers, restricted or blocked tidal flows, obstructed fish passages, channelized and buried coastal streams, and colonization by invasive species. The elimination or restriction of tidal flows alters water chemistry, sediment accretion rates, and the export of organic matter. Changes in species composition, including the spread of invasive species such as Phragmites , often accompany hydrologic and soil chemistry alterations caused by tidal restrictions. Degraded coastal wetlands have a reduced capacity to assimilate pollutants, buffer storm damage, support native biota, provide opportunities for human use and enjoyment, and respond to sea level rise.

Why Restore Coastal Wetlands?
Humans have interacted with salt marshes for hundreds of years. However, only recently has society recognized the ecological and social benefits of salt marshes and other wetlands, and supported efforts to protect and restore them. It is now understood that the functions provided by wetlands - including flood storage, water quality improvement, protection from storm damage, provision of wildlife habitat, and recreational opportunities - are invaluable, and that the preservation of wetlands is more economically efficient than trying to mitigate impacts after wetlands are degraded or lost. Massachusetts has strict laws that protect wetlands and regulate development impacts, and wetland restoration is increasingly regarded as a major tool for improving the function of degraded wetlands and increasing wetland acreage. The goal of wetland restoration is to bring back wetland values and functions that have been lost due to historic human impacts.

The potential wetland restoration sites identified in the Draft Plan provide opportunities for pro-active wetlands restoration. Under pro-active restoration, property owners voluntarily participate in wetland restoration projects. With numerous federal, state, and private funding sources available, restoration work may be able to proceed with little or no cost to property owners. The communities of the Great Marsh Region, along with all who benefit from its aquatic habitats, have a strong interest in restoring these habitats when such opportunities arise.

It is important to point out a few definitions here. For purposes of the Plan, the following apply-

• Coastal wetlands are wetlands which are tidally influenced, formerly tidally influenced, and/or associated with diadromous fish passages. Coastal wetlands may include, but are not limited to, riparian wetlands, freshwater or brackish tidal marshes and swamps (may be tidally restricted or head-of-tide wetlands), salt marshes, salt ponds and impoundments, mud-flats, and sub-tidal aquatic beds.
• Pro-active restoration projects are those that are undertaken primarily for environmental benefit and are not associated with any permit condition or compensatory mitigation requirement. Many potential restoration sites identified in the Plan are ideal for pro-active restoration projects.
• Compensatory wetland restoration is conducted to mitigate the unavoidable impacts to wetlands of a permitted activity or can be required under an enforcement order to replace wetlands that have been illegally destroyed. Several sites identified in the Plan (primarily filled, former marshes) may be suitable for compensatory mitigation projects or for supplemental environmental projects required by regulatory authorities.
• Wetland restoration, enhancement, and creation - "Restoration" means restoring a wetland that has been completely lost, such as by removing material that was used to fill in a former salt marsh. "Enhancement" means improving the condition and ecological function of an existing yet degraded wetland. "Creation" means creating a wetland in a place where none existed historically. The terms "restoration" and "enhancement" are compatible, for the purposes of this document.

This Draft Plan is based on the collaborative work of many partners in the Great Marsh Region. See our Partnerships page for more information on this collaborative effort and the Methodology page for details on how the Plan was compiled.