A.
Chapter 237, Wetlands Protection, of the General Ordinances of the Code of the Town of Barnstable, explicitly protects the values of the natural resources of its foreshores, intertidal areas and the Commonwealth of Massachusetts' tidelands and waters as well as inland wetlands, ponds and lakes.
B.
The purpose of these regulations is to establish performance standards for private docks and piers. The authority for these regulations derives from Chapter 237, Wetlands Protection, of the General Ordinances of the Code of the Town of Barnstable § 237-8. These regulations will not apply to freshwater docks unless the Commission specifically finds that they are applicable.
C.
The construction, use, and maintenance of docks, piers and walkways are likely to have a significant or cumulative adverse effect on the wetland resource values of storm damage prevention, fin and shellfisheries, wildlife habitat, erosion and sediment control, and recreation. Construction, maintenance and use of piers can have adverse effects on resource areas and on the use of these areas for recreational purposes. Further, piers destroyed by storm pose a threat to nearby properties by increasing water-borne debris.
D.
Turbulence, such as caused by jet-drive boats, and propeller dredging generated by boat use associated with piers significantly increase turbidity levels. High turbidity levels attenuate light. Light is necessary for photosynthetic process responsible for the primary productivity and oxygen regeneration of the water. The suspended sediments settle on shellfish beds, smothering existing shellfish and altering the quality of the benthic environment essential for spat (mollusk larvae) settlement. Resuspension of bottom sediments causes redistribution of sediments, alteration in sediment grain size distribution and causes changes in bottom topography relief, elevation and grade, including creation of depressions in the bottom. Settlement of sediments into depressions can create deep pockets of highly fluid-like sediment which may not be able to physically support shellfish or which can become anoxic and therefore not support shellfish. Disturbance of sediments during the period of shellfish larval settlement hinders or prevents the effective settlement of shellfish larvae. Boat traffic generated from piers will add to this disruption and may cause erosion of banks and marshes.
E.
Construction of piers and subsequent boat activity causes resuspension of nutrient-laden sediment particles which may cause a release of sediment-bound nutrients to the water column resulting in a "bloom" of vegetation. Release of nutrients to the water column leads to eutrophication and anoxic bottom conditions. Anoxic sediments and anoxic bottom conditions create adverse impacts on benthic resources, including shellfish and fisheries.
F.
While pier construction is typically the least environmentally destructive method of crossing a marsh, it may adversely affect the physical characteristics and functional value of marsh. Marsh plants provide the major energy flow (detritus food chain) between the autotrophic and heterotrophic levels in a marsh-estuarine system. Many species of sport and commercial fish and shellfish are dependent upon this system. Plants adapted to high ambient light intensity, such as marsh grasses, are ill-adapted to the shaded conditions created by a pier. Shading may result in the loss of vegetation biomass (decreased plant height, population density, and leaf thickness) or alteration of species composition. Reduction in plant density results in the loss of sediment normally trapped by roots and culms. Tidal washout of sediment can result in localized depressions which, through evaporation of trapped water, concentrate salt. High sediment salt levels effectively preclude recolonization by original vegetation. Localized tidal washout may lead to further vegetative regression, erosion, and disruption of natural communities in the area.
G.
Propeller turbulence near or in areas of submerged aquatic vegetation, such as eel grass, or salt marsh damages vegetation, thereby increasing the rate at which organic detritus is produced. If this organic detritus does not completely decompose aerobically, then anoxic bottom conditions will ensue, which adversely impact shellfish and fisheries.
H.
Cumulative impacts of the construction, maintenance and use of piers threaten to decrease the overall productivity of the marsh ecosystem, to reduce its ability to absorb storm wave energy, and to reduce its contribution to groundwater and surface water quality. Cumulative impacts also affect shellfish habitat and shell fishing.
I.
Docks and piers when placed in land containing shellfish or shellfish habitat have an adverse impact on the resource area value of recreation. The placement, length and size of docks and appurtenant floats can interfere with the harvesting of quahogs, soft-shell clams, and scallops. Docks and piers can have an unacceptable significant or cumulative effect on habitat and recreation as defined in § 327-14 of Chapter 237, Wetlands Protection, of the General Ordinances of the Code of the Town of Barnstable.
J.
Piers, depending on their length, can have an adverse impact on recreation by interfering with recreational boating activities. Not properly designed, piers can interfere with intertidal lateral access for recreational fishing and fowling. Any proposal that affects navigation is likely to have a significant or cumulative adverse effect on recreation. Excessive lighting on piers may cause temporary "night blindness" in boaters and may disrupt feeding habits of nocturnal aquatic animals.
K.
Docks conforming to the following regulations can be presumed to minimize the aforementioned possible negative impacts.