State regulations that took effect Oct. 1 should make it easier to determine where state jurisdiction ends and town jurisdiction begins in coastal areas.
Brian Thompson, director of the Office of Long Island Sound Programs at the state Department of Energy and Environmental Protection, said the new law, passed by the General Assembly last year, sets the jurisdictional boundary according to elevation, a standard that will be more consistent and precise given rising sea levels.
Under previous regulations, the high tide line, determined by wrack lines, vegetation patterns and other evidence, established whether a coastal area or tidal riverbank was under state or town control. Instead of state control below the high tide line, the state now governs permits for structures such as docks and seawalls as well as activities such as dredging below certain elevations that vary by town. Above that elevation, towns have jurisdiction.
"This was done in response to issues generated by (Tropical Storm) Irene last year," Thompson said Tuesday. "It also encourages towns to look at sea level rise and its potential impacts in the planning process."
In southeastern Connecticut, the jurisdiction line on the Long Island Sound coast ranges from 2.9 feet in Old Saybrook to 2 feet in Stonington. Along the Thames River, the line ranges from 2.1 feet in New London to 2.4 feet in Norwich. On the lower Connecticut River, it ranges from 2.9 feet in Old Lyme to 2.8 feet in Essex. The point where the coastline reaches the elevation listed for each town would be determined by a surveyor, Thompson said.
"This is a much more certain approach," he said.
According to the National Oceanic and Atmospheric Administration, sea level has been rising about 4 millimeters per year at the New London tide gauge since 1980.
Thompson said the law also sets a state policy favoring "living shorelines" along the Connecticut coast, encouraging the creation of oyster reefs or marshes to buffer wave energy rather than using hard structures such as sea walls and riprap.