DEEP: Tidal Wetlands - General Information

Tidal Wetlands - General Information

What are tidal wetlands?

Tidal wetlands are "those areas which border on or lie beneath tidal waters, such as, but not limited to banks, bogs, salt marshes, swamps, meadows, flats, or other low lands subject to tidal action, including those areas now or formerly connected to tidal waters, and whose surface is at or below an elevation of one foot above local extreme high water; and upon which may grow or be capable of growing some, but not necessarily all, of [a list of specific plant species - see Connecticut General Statutes (CGS) section 22a-29(2) ]"  [CGS section 22a-29, as referenced by CGS section 22a-93(7)(E)]. In general, tidal wetlands form in "low energy" environments protected from direct wave action. Low marsh areas are flooded by tidal waters twice a day, while high marsh areas are flooded a few times a month. All tidal wetlands support a diverse ecosystem of vegetation and wildlife.

Detailed information about the geology, history, ecology and restoration of tidal wetlands can be found in the publication entitled "Tidal Marshes of Long Island Sound."

Why are tidal wetlands valuable?

Tidal wetlands are areas of high nutrient and biological productivity that provide detritus, decaying organic matter, that forms the base of the food chain in tidal wetlands. Next to tropical rainforests, tidal wetlands are the most biologically productive resource in the world. Tidal wetlands provide habitat, nesting, feeding, and refuge areas for shorebirds; serve as a nursery ground for larval and juvenile forms of many of the organisms of Long Island Sound and of many estuarine-dependent oceanic species; and provide significant habitat for shellfish. Most of the commercial fisheries stock that we eat start their lives in tidal wetlands. These resource areas also improve water quality by trapping sediments, reducing turbidity, restricting the passage of toxics and heavy metals, decreasing biological oxygen demand (BOD), trapping nutrients, and buffering storm and wave energy. Tidal wetland vegetation stabilizes shorelines and buffers erosion. Tidal wetlands provide recreational opportunities for fishing, wildlife observation and hunting; are important to commercial and recreational shell- and finfisheries; and are areas of scientific and educational value. Tidal wetlands are a major source of coastal open space and offer exceptional scenic views. 

Why do tidal wetlands need protection?

Due in part to their transitional location between upland areas and coastal waters, tidal wetlands are very specialized habitats that are sensitive to disturbance. Human actions, both direct and indirect, can adversely impact tidal wetlands and their functions. Direct actions include activities such as filling, dredging and trampling; indirect actions include upland uses that result in sedimentation, increased stormwater discharge, proximate septic system failures or the installation of culverts in a manner that decreases salt water flushing. In these cases, the delicate balance between soil surface, water level, water quality and/or salinity is disturbed. This results in a stressed habitat which is usually less productive than a healthy marsh and frequently supports undesirable species, most typically Common Reed (Phragmites australis). Historically, many of these activities have occurred in Connecticut resulting in the loss or degradation of the majority of tidal wetlands. As a result it is even more important to protect the wetlands that remain. 

Does the DEEP regulate activities on tidal wetlands?

Yes. The Department of Energy and Environmental Protection (DEEP) has direct regulatory jurisdiction over activities occurring in tidal wetlands and/or waterward of the high tide line. If any construction activities or structure(s), in part or in whole, or any incidental work proposed in conjunction with the construction of structure(s) is proposed at or waterward of the high tide line, authorization from the DEEPís Office of Long Island Sound Programs would be required prior to construction in accordance with the Tidal Wetlands Act (CGS sections 22a-28 through 22a-35) and/or the statutes governing the placement of structures, dredging, and fill in tidal, coastal or navigable waters (CGS sections 22a-359 through 22a-363f, inclusive).

What are municipal responsibilities toward tidal wetlands?

Although activities within tidal wetlands are regulated by the DEEP, municipalities are responsible for ensuring that adjacent upland development does not harm these resource areas. The Connecticut Coastal Management Act contains policies and standards regarding tidal wetlands that must be applied during municipal coastal site plan review process. Generally speaking, land use boards and commissions in coastal municipalities must ensure that development will not result in degradation of tidal wetlands, and that tidal wetlands are preserved, protected and, to the extent practicable, restored.

What are the statutory polices that apply to tidal  wetlands?

It is declared that much of the wetlands of this state have been lost or despoiled by unregulated dredging, dumping, filling and like activities and despoiled by these and other activities, that such loss or despoliation will adversely affect, if not entirely eliminate, the value of such wetlands as sources of nutrients to finfish, crustacea and shellfish of significant economic value; that such loss or despoliation will destroy such wetlands as habitats for plants and animals of significant economic value and will eliminate or substantially reduce marine commerce, recreation and aesthetic enjoyment and that such loss or despoliation will, in most cases, disturb the natural ability of tidal wetlands to reduce flood damage and adversely affect the public health and welfare; that such loss or despoliation will substantially reduce the capacity of such wetlands to absorb silt and will thus result in the increased silting of channels and harbor areas to the detriment of free navigation. Therefore, it is declared to be the public policy of this state to preserve the wetlands and to prevent the despoliation and destruction thereof [CGS section 22a-28 as referenced by CGS section 22a-92(a)(2)].

To preserve tidal wetlands and to prevent the despoliation and destruction thereof in order to maintain their vital natural functions; to encourage the rehabilitation and restoration of degraded tidal wetlands; and where feasible and environmentally acceptable, to encourage the creation of wetlands for the purpose of shellfish and finfish management, habitat creation and dredge spoil disposal [CGS section 22a-92(b)(2)(E)].

To disallow any filling of tidal wetlands and nearshore, offshore, and intertidal waters for the purpose of creating new land from existing wetlands and coastal waters which would otherwise be undevelopable, unless it is found that the adverse impacts on coastal resources are minimal [CGS section 22a-92(c)(1)(B)].

To disapprove extension of sewer and water services into developed and undeveloped beaches, barrier beaches and tidal wetlands except that, when necessary to abate existing sources of pollution, sewers that will accommodate existing sues with limited excess capacity may be used [excerpt from CGS section 22a-92(b)(1)(B)].

In addition, the Connecticut Coastal Management Act defines as an adverse impact:

Degrading tidal wetlands, beaches and dunes, rocky shorefronts, and bluffs and escarpments through significant alteration of their natural characteristics or functions [CGS section 22a-93(15)(H)]

Degrading or destroying essential wildlife, finfish or shellfish habitat through significant alteration of the composition, migration patterns, distribution, breeding or other population characteristics of the natural species or significant alterations of the natural components of the habitat [CGS section 22a-93(15)(G)].

During the coastal site plan review process, a determination must be made that adverse impacts have been avoided and unavoidable adverse impacts have been minimized in order to lawfully approve the application. (See the Coastal Site Plan Review and Adverse Impacts fact sheets for additional information.)