In North and South Carolina, the National Wetlands Inventory (NWI) estimates there are 8.1 million acres (over 12,600 square miles) of wetlands, with 4.2 million acres in North Carolina and 3.8 million acres in South Carolina. This means that wetlands account for about 14% of the land area in North Carolina and almost 20% of South Carolina!

Most of these wetlands are found in the coastal plain, with only 4.8% in the piedmont and less than 0.2% in the mountains. That means these wetlands are even more important because they are critical hydrologic components of the watershed and provide habitats for threatened and endangered species. Click here to view a map of all the wetlands in the Carolinas.

In terms of vegetation type, Carolina wetlands are mostly freshwater forested or shrub-covered (87%) with only 4% as freshwater emergent/herbaceous marsh vegetation and 9% estuarine/marine marsh vegetation .

Estuarine and Marine Wetland: 708,635 acres (8.8%)

Freshwater Emergent Wetland: 341,030 acres (4.2%)

Freshwater Forested/Shrub Wetland : 7,016,716 acres (87%)

Other Wetlands: 549 acres (<1%)

Total:  8,066,929 acres

In 2011, the U.S. Environmental Protection Agency (EPA) embarked on the first national scale evaluation of the ecological condition of U.S. wetlands called the National Wetlands Condition Assessment (NWCA). Close to 1,000 wetland sites were randomly chosen across the  U.S. Forty-seven (47) sites in North Carolina and 40 sites in South Carolina were surveyed which is reflective of the fact that North and South Carolina have the third and fourth highest amount of wetland lands in the conterminous U.S. behind Louisiana and Florida. 

The condition of wetlands in North and South Carolina was similar with the majority of the wetlands sampled in good condition.

North Carolina 

• 57% rated good 
• 28% rated fair 
• 15% rated poor

South Carolina

• 55% rated good
• 25% rated fair 
• 20% rated poor

Source: US EPA, National Wetland Condition Assessment

Based on U.S. Environmental Protection Agency (EPA)’s 2011 National Wetlands Condition Assessment (NWCA), the leading stressors in wetlands were caused by physical disturbances to wetlands and their surrounding habitat. The leading stressors for our wetlands are as follows:

North Carolina

• 26% Ditching 
• 9%    Non-native vegetation
• 6%    Compacted soils 
• 4%    Vegetation loss or removal  

South Carolina

• 23% Vegetation loss or removal 
• 18% Ditching
• 10% Compacted soils
• 3 %  Non-native vegetation

Source: US EPA, National Wetland Condition Assessment

Carolina wetlands provide a host of valuable ecosystem services to human and other residents. Most (over 85%) of Carolina wetlands are wetland forests and a recent study by the Dogwood Alliance conducted a state-by-state valuation of the services that wetland forests provide in the southeast. Exhibit 3 totals and presents the ecosystem services provided by forested wetlands in the Carolinas. In total, the study estimates that wetlands provide almost $70 billion in ecosystem services to North and South Carolina citizens.

Exhibit 3. Ecosystem Services Provided by Forested Carolina Wetlands

• Protection from extreme events: $20 B.
• Aesthetics, recreation, tourism: $16 B.
• Water filtration/treatment: $15 B.
• Food/pollination: $ 9.5 B.
• Regulating services: $ 5.9 B.
• Total: $67 B.

Examples of the ecosystem services performed by Carolina wetlands include:

Protection from extreme events. Wetlands help shelter and protect coastlines and inland areas from damage from storm surge and help mitigate flooding from excess rainfall.

Water filtration and treatment. Wetlands can improve water quality by fixing nitrogen, retaining phosphorous, and filtering out sediment and toxic metals.  

Regulating services. Wetlands regulate water flow and landscape hydrology by contributing dynamic water storage during high flows and limiting peak flow frequency, magnitude, and duration. Wetlands are also central to carbon cycling in the environment, serving as a primary sink for sequestering carbon across the landscape.

Food/Pollination. As wildlife refuges and critical supporting habitats for fish and shellfish, wetlands support recreational hunting and commercial and recreational fishing in the Carolinas.

Aesthetics, Recreation, and Tourism. Wetlands are beautiful and offer great places to hike and paddle. Examples of great wetlands to visit are our Wetland Treasures of the Carolinas. 

As the Carolinas get warmer and wetter, wetlands provide numerous benefits and services related to mitigating negative impacts of a changing climate.

• Wetlands sequester carbon – in trees and shrubs, and in the peat that accumulates in them
• Wetland forests cool the landscape and improve regional microclimates
• Wetlands protect against storm damage from increasing winds and storm surge
• Wetlands mitigate flooding and regulate flow as rainfall increases & sea levels rise

Wetlands also are affected by climate change. For example

• Coastal freshwater wetlands are vulnerable to sea level rise and stronger, slower, and more frequent storms.
• Floods can wash out sequestered carbon
• Rising temperatures can change species compositions by eliminating cool-weather species.
• Drought can change wetlands to dryland and eliminate the hydroperiods critical to wetland health
• Change in temperature and precipitation can favor invasive species

Active research across the Carolinas is ongoing on how climate change impacts wetlands and how wetlands can impact climate change. 

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