Tidal Marsh Restoration
Type of Development
Dependent on scale.
Tidal marsh restoration is the restoration, maintenance, and protection of tidal marshes and tidal flats through added sediment and planted vegetation. The restoration involves a multi-step process of planting native and salient (salt-water friendly) plants and adding sediment to restore tides and connect marshes to adjacent environments, including the greater watershed. First, planting native, salient plants accelerates the colonization of healthy plants, reduces erosion from tides through wave dampening, and encourages organisms to live, grow, and flourish within the ecosystem. Second, adding sediment creates elevated areas to provide high-tide refuge for endangered and native animals as sea levels rise, and also helps to cycle through fundamental nutrients. Third, restoring tidal action to diked baylands restores the tidal marsh ecosystem by reducing stagnant, unfiltered, polluted water.
Tidal marsh restoration elevates land, restores habitats, and dampens wave volume and impact.
In addition to sustaining food for habitats, tidal marshes help to manage the strength and velocity of waves through shoaling and the friction of vegetation, dampen storm surges, and protect adjacent infrastructure and habitats from rising seal level. For example, tidal marshes control the erosion of levees, which allows levees and seawalls to be built lower.
Hydraulic connections will determine the sediment and water supply. Land ownership is important to keep in mind when finding sites.
Since the salinity of the water will change over time, plants must be salinity resistant. While tidal marshes can act as wave dampeners, factors such as wave size, wavelength, and vegetation characteristics (canopy height, density, stem diameter, and stiffness) can impact the effectiveness of wave dampening. For example, higher waves are dampened better than low waves.
Within the first few months, maintenance is required to ensure that planted vegetation is rooted and stable. If the planted vegetation is not rooted and stable, there is a need to continue a sediment supply until the ecosystem can sustain itself. While other maintenance is not required, tracking the progress of restored tidal marshes is valuable for future projects. Little to no maintenance is expected after 2 years.
Dependent on scale.