Building a resilient coastline: Study suggests seawalls, elevated roads and other options
In the coming years, Milford may have to consider constructing seawalls, elevating coastal roads, elevating more homes and taking other steps to make its shoreline safer from flood hazards.
These are some of the ideas and proposals contained in a 200-page draft report about increasing Milford’s coastal resilience, which will be discussed at an informational meeting on Tuesday, March 29, at 7 p.m. at the Parson’s Building Veterans Memorial Auditorium.
This is the second informational meeting about developing a citywide Coastal Resilience Plan.
At the initial meeting held in January, residents and business owners in Milford discussed types of coastal hazards the city is facing and will face in the future, and learned about the available methods of adapting to a changing coastal environment to become more resilient to tidal flooding, storm surges, sea level rise, and coastal erosion.
This week, residents and business owners in Milford will have a chance to learn more about the available methods of adapting and how they may be applied in Milford, and they can have a look at the city’s draft Coastal Resilience Plan for adapting to coastal risks over the long term.
The draft plan
“The City of Milford has over 53,358 residents (as of 2014) living within 22.2 square miles of land,” the report begins. “The city has over 17.5 miles of shoreline along Long Island Sound and the tidal Housatonic River estuary. Recent events such as Tropical Storm Irene and Hurricane Sandy have underscored the risks associated with occupying coastal areas, and highlighted the fact that property owners and municipalities bear a heavy financial burden to recover from these types of events.”
The plan presents citywide and location‐specific options that are available to adapt to changing conditions and to prepare for future storms.
The report was prepared by Milone & MacBroom Inc. under the direction of the City Milford Hazard Mitigation Committee. The United States Department of Housing and Urban Development’s (HUD) Community Development Block Grant Disaster Recovery Program (CDBG‐DR) funded the report.
“Coastal storms may be increasing in frequency, and periodic high tide flooding will increase in frequency as sea level continues to rise,” the report states. “Thus, even if coastal vulnerabilities remain static, risks will increase.”
Milford's neighborhoods already have experience dealing with coastal hazards, the report notes. The neighborhoods of Milford Point (Cedar Beach) and Bayview Beach regularly experience flooding at especially high high tides, “such as those associated with low‐pressure systems or full‐ or new‐moon conditions.” Residents suffer from blocked access to homes and damage to property and vehicles on a regular basis in those locations.
“Wildemere Beach has seen its sandy shoreline eroded to gravel and cobbles and has often taken damage from storms,” the report states. “Trumbull Avenue and Gulf Beach Road have to be regularly maintained to prevent failure due to erosion by high waves. Aged tide‐controlled drainage systems have led to problems at Bayview Beach and Point Beach. Rising waters and increasing storm severity and frequency will exacerbate these problems and give rise to as yet nonexistent problems in other parts of town.”
The plan identifies different areas of Milford, which are subject to their own unique set of risks. It also outlines various controls, including the construction of seawalls, bulkheads, groins, offshore breakwaters, sand dunes and artificial reefs.
The draft plan also considers elevating coastal roads, floodproofing wastewater treatment plants and sewer pumping stations, as well as elevating more homes and retiring some roads.
For example, the report suggests acquiring “properties at the ends of dead‐end roads that extend into tidal wetlands, thereby reducing the risks faced by emergency management personnel. Examples include the north ends of finger roads extending from East Broadway in Silver Beach.”
A tide gauge in Bridgeport collected data between 1964 and 2014, and indicated that mean sea level (MSL) has been increasing at a rate of 2.87 millimeters (0.11 inch) per year, which is equivalent to a rise of 0.94 feet over 100 years, the report states. Another station in New London suggests an increase of 0.85 feet per 100 years, based on measurements since 1938.
“The United States Geological Survey (USGS) has demonstrated that sea levels along the mid‐Atlantic and northeast coasts of the United States are already rising three to four times faster than the global average since 1990,” the report states. “This heightens the need for resilience planning in Milford.”
According to the comprehensive document, the most vulnerable aspects of Milford’s coastal area are its residential structures, its infrastructure and utilities, and its natural systems.
“Homes are vulnerable to inundation from Long Island Sound, erosion, failed drainage infrastructure, and damage from water and high winds,” the report states. “Many coastal roads are vulnerable to being submerged by rising waters or eroded by waves.”
The draft plan concludes by saying that risks along Milford’s coastline will likely increase over time from water and wind.
“Milford’s coastal neighborhoods are diverse and each will be faced with a combination of vulnerabilities with sea level rise and the increased incidence and severity of coastal storms,” the report states.
To build resiliency, the draft plan says Milford should review the most feasible and prudent alternatives for adaptation.