FACTORS INFLUENCING THE IMPACTS OF STORM WAVES ON THE FETCH-LIMITED SHORELINE OF CONNECTICUT DURING HURRICANES IRENE AND SANDY

The Connecticut shoreline is one of the most intensively developed in the country. Much of this development is now at high risk, primarily because the patterns and policies of development were uninformed by an understanding of the coastal dynamics of a formerly glaciated, fetch-limited shoreline.

The Connecticut coast has commonly been thought of as “protected” by the presence of Long Island, New York. Despite this protection, Irene and Sandy imposed significant property losses on coastal cities. The Cosey Beach area of East Haven, for example, received national press coverage, losing some 28 houses along a 4,000-foot beachfront. The most severe damages, not surprisingly, were due to wave impact. Factors such as land elevation and engineering adaptations played a role in the severity of wave impacts, but the overriding factor was beach width. Small differences in beach width proved to be significant during Irene and Sandy. At Cosey Beach, a beach width differential of 40 feet in two adjacent homes made the difference between massive damages and minor basement flooding.

Three fundamental factors convolve to put the shoreline structures and infrastructure of this “protected” coast at risk. 1) Coastal Connecticut is naturally erosive. Sheltering by Long Island actually exerts a harmful effect on beach equilibrium. Fetch limitations are insufficient to prevent coastal erosion during strong storms. Fetch limitation does, however, preventonshore transport during fair weather because the wave field lacks threshold and cumulative energy. 2) Prior to development, natural beaches were maintained by erosion of glacial soils along the shoreline. Concern about this erosion accompanying development led to a proliferation of seawalls. The result was net beach erosion (> 1ft /yr. in some locations). A combination of interference with sand sources and the erosive impacts of seawalls themselves caused the loss of the beaches that development originally relied on for buffering against storm waves. 3) Rising sea level and storm intensification associated with climate change.

Climate change in particular makes rethinking of current coastal practices (e.g. direct shoreline construction), assumptions (e.g., protection by Long Island), and policies (e.g., local home rule) urgent.