§ 196A-9A. Land Subject to Coastal Storm Flowage

A. Preamble

Land Subject to Coastal Storm Flowage – including but not limited to coastal beaches, salt marshes, banks, barrier beaches, salt ponds, dunes, land containing shellfish, land under the ocean, and banks of and land underlying fish runs – is important for the protection of public and private water supply, groundwater and groundwater quality, flood control, erosion and sedimentation control, storm damage prevention, water pollution prevention, wildlife habitat, fisheries, shellfish, and to the interests of aesthetics and recreation.

Land Subject to Coastal Storm Flowage extends from mean low water to the calculated extent of a 100-year storm. During extreme high tides and hurricanes the ability of the land to absorb flood waters is important to buffer inland areas from flood and wave damage. The more gentle and permeable a seaward-sloping land surface is, the more effective that land surface is in reducing the height and velocity of incoming storm waves. Dredging of land subject to coastal storm flowage has the potential of allowing storm waves to break further inland and to impact other areas which might not otherwise be affected. Filling of land subject to coastal storm flowage is likely to cause displacement of flooding consequences to other areas.

Those portions of coastal floodplains which are immediately landward of salt marshes, coastal beaches, barrier beaches, coastal dunes, or coastal banks, require special protection. As sea level rises, these areas will be inundated more frequently by storm and tide. Activities carried out within these traditional areas may interfere with the natural landward migration of the adjacent coastal resource area.

B. Presumption

Where a project involves removing, filling, dredging or altering land subject to coastal storm flowage, the Commission shall presume that such an area is significant to the following interests specified both in §196A-1B of these regulations and 310 CMR10.57 (1)(a)(b): the protection of public and private water supply, groundwater and groundwater quality, flood control, erosion and sedimentation control, storm damage prevention, water pollution prevention, wildlife habitat, fisheries, shellfish, and to the interests of aesthetics and recreation.

C. Performance Standards

A proposed project that may result in alteration of land subject to coastal storm flowage shall not cause or create the likelihood of the following:

1. Reduction in the ability of the land to absorb and contain waters.
2. Reduction in the ability of the land to buffer more inland areas from flooding and wave damage.
3. Displacement or diversion of flood waters to other areas.
4. Damage to other structures or property.
5. Pollution of groundwater, surface water, or salt water.
6. Reduction of an area’s capacity to provide for wildlife.
7. An increase in the elevation or velocity of flood waters.
8. Prevention of the migration of resource areas such as salt marshes due to sea level rise.