Breathing Room for Wetlands: Buffers Protect Wetland Benefits

Wetlands are a prominent feature on the South Carolina coastal landscape. Wetland is an umbrella term and encompasses many different types of habitat. A tour of local wetland ecosystems might include drifting past cypress-tupelo swamps in black water rivers, stomping through dense pocosin shrubs in a Carolina Bay, or pulling your boots out of pluff mud in a salt marsh.

Wetlands provide benefits including flood mitigation, wildlife habitat, nutrient cycling, water quality improvements, carbon storage, groundwater recharge, and more. These valuable services are important to local communities, leading to interest in policies that would ensure these benefits are maintained or enhanced. In particular, state and local governments have the ability to go above and beyond the baseline of existing wetland protections. At the federal level, wetlands are protected under Section 404 of the Clean Water Act. The boundaries that determine jurisdictional limits may not be sufficient to maintain desired levels of wetland benefits. For example, construction, mining, or industrial activities may not have direct impacts within wetland boundaries, but can indirectly affect these ecosystems. Common impacts from human activities include altered hydrology, influxes of eroded sediments, or excessive nutrients.

So how can wetlands be protected from these impacts? One of the best ways to do this is to give them some breathing room! Wetland buffers add a layer of protection around wetlands, shielding them from adjacent impacts. For example, imagine the noise of a neighbor’s leaf blower spilling over into your backyard, even if they are not working directly in your space. Having a border of plants can help to muffle that outside noise, acting as a buffer. Buffers are non-disturbance areas where natural vegetation is maintained. This differs from setbacks, which define a distance from a boundary where certain activities are prohibited. Vegetated buffers provide similar functions to wetlands (filtering runoff, providing habitat), which reduces the intensity of impacts to the core wetland. Wetland ecosystems can only provide services up to a certain point before they themselves become degraded and their functions are impaired.

To put buffers into practice, local governments may enact ordinances requiring buffer zones where development borders wetlands. Wetland buffers can come in different shapes and sizes. Determining the appropriate width for a buffer depends on many factors, including the desired wetland benefits, the intensity of the nearby activity, the characteristics of the site, or the sensitivity of the habitat. For example, wider buffers (50 feet or more) are needed to maintain wetlands as wildlife habitat. A smaller buffer may still provide some benefit for filtering sediment and pollution before it enters the wetland, but it wouldn’t provide habitat connectivity. As a general rule, the wider the better for maintaining wetland benefits!

To provide science-based information on buffers for coastal decision-makers, the NERR Coastal Training Program developed a Fact Sheet on Wetland Buffers. Additional resources for learning more about wetlands and buffers are below: