CRMC: Federal flood maps flawed

BEACH WEATHER: A machine clears sand off Atlantic Avenue in the Misquamicut area of Westerly in the days following Superstorm Sandy in 2012. / PBN FILE PHOTO/BRIAN MCDONALD
BEACH WEATHER: A machine clears sand off Atlantic Avenue in the Misquamicut area of Westerly in the days following Superstorm Sandy in 2012. / PBN FILE PHOTO/BRIAN MCDONALD

New federal flood maps have made it difficult for some Rhode Island property owners to sell, insure or rebuild their houses, but state officials say the maps still understate how vulnerable beachfront communities are to future storms.
Returning to unresolved concerns first expressed in the wake of Superstorm Sandy, the R.I. Coastal Resources Management Council this fall has renewed its call for a re-evaluation of the new flood maps for Washington County.
The council sent letters in August and October to the Federal Emergency Management Agency asking the federal agency to consult with them on whether the maps conflict with the state’s federally approved coastal-management policies.
“We have a number of concerns with the techniques and data used,” Grover Fugate, executive director of the CRMC, told Providence Business News. “The flood elevations near shore are actually being lowered from previous estimates in some places, and we believe that there are errors in modeling.”
Specifically, Fugate said there are problems with the models used to calculate the power of wind and waves driven by severe storms right along the state’s south-facing beaches. (Much of the debate about the new flood maps has involved inland or Narragansett Bay neighborhoods.)
Those alleged errors include estimating coastal wind speeds based on inland readings, underestimating the size of the ocean swells in Block Island Sound and overestimating the protection beaches will provide in deflecting those swells.
These concerns come roughly a year after Fugate first wrote to the consortium of companies that helped redraw the flood maps for FEMA.
“This is particularly important now as we have suffered extensive damage along the Rhode Island south shore from [Superstorm] Sandy,” Fugate wrote in a Nov. 4, 2012 letter to FEMA about the maps. “Our concern is that even in moderate storms, we experience a total loss of dune systems that is not reflected in your models. Dunes are an important first line of defense, providing a natural storm buffer.”
In February, FEMA brushed off the state’s concerns, writing that the only way the maps could be appealed would if they were found to be “scientifically or technically inaccurate,” which it said they were not and restated the procedures used to make them. The CRMC didn’t let it go, however, responding in August with a formal request for a “determination of consistency,” an administrative procedure to make sure new federal rules do not conflict with approved state coastal-management policies.
FEMA did not respond to the August letter, so in October Fugate repeated the request, but has again received only silence.
CRMC spokeswoman Laura Dwyer said the council is now weighing its options and “may pursue this further.” That could include petitioning the National Oceanic and Atmospheric Administration to act as a mediator between the state and federal government.
While many property owners near the beach are relieved the new maps didn’t include them in flood plains, more lenient maps potentially complicate the state’s decisions about where to build up shoreline defenses to protect homes, businesses, roads and public infrastructure.
The debate last year about building a sea wall to protect businesses and the road leading to the Matunuck section of South Kingstown still hasn’t been permanently settled and could be reprised in other beachfront areas of the state.
And Rhode Islanders living inland, some of whom have been forced to buy costly insurance because of the new maps, will wonder if they are unfairly subsidizing waterfront owners.
Then there are the environmental questions.
“The purpose of the national flood-insurance program is not only to protect people for loss in aftermath, but should also be to inform new buyers and decision-makers of the risks in living and rebuilding in flood-prone areas,” said Tricia Jedele, vice president and director of Conservation Law Foundation Rhode Island. “We have had significant flood events and loss of property along both rivers and in coastal areas that are now having to face questions about infrastructure and putting in walls to protect roads and drinking-water systems. CLF thinks it is a good time to re-evaluate the flood-insurance program and whether we are using the best possible data to generate maps and what incentives we are creating to live in these areas.”
About five years ago, Rhode Island began putting together an ocean-planning guide, approved by the federal government in 2011 and known as the Ocean SAMP, that involved collecting large amounts of information about the waters just off the coast. The research that went into that document, much of it compiled by University of Rhode Island scientists, forms the basis for many of the Coastal Resources Management Council issues with the new federal flood maps.
In the post-Sandy letter last November, Fugate said the federal models using 15-foot-maximum wave heights are far too low and have been exceeded “four to eight times” over the last four years. Both Irene and Sandy produced waves of more than 30 feet at the Block Island buoy, the letter said.
And a continuing concern, as happened in Sandy, Rhode Island beaches and dunes erode much faster in severe storms than the map-makers project, leaving the coast with less material to break incoming waves.
“Our dunes get taken out in the first hours of storms,” Fugate said. “They are gone and are not there to trip the waves. We believe this is a serious underestimation.”
In addition to determining who needs to buy flood insurance, in Rhode Island the flood maps are used in local building codes that require the lowest floor of a new structure to be at least 1-foot above the base flood elevation.
Lifting houses up on pilings, while not a perfect solution, has been proven to significantly reduce losses in bad coastal storms, Fugate said.
The elevations in the federal-rate maps are supposed to represent the flood plain during a 100-year storm, or a storm that has a 1 percent chance of hitting an area in any given year.
Fugate cautioned that none of the storms that hit the region in recent years, including Sandy, were 100-year storms, the last of which was the Hurricane of 1938. In Westerly, the remnants of Sandy had sustained winds of 58 mph and a storm surge of 5 feet, while the Hurricane of 1938 had sustained wind of 115 mph and a storm surge of more than 17 feet.
“Because we had Sandy, Irene and Bob, which were benign from a coastal perspective, that may lull people into a sense of security in hurricanes,” Fugate said. “There aren’t many people around who remember 1938.” •

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