U.S. Flood Elevation Rules For Home Building Called Inadequate

NU Online News Service, Sept. 14, 3:46 p.m. EDT

Government minimum flood elevation requirements for Gulf Coast region properties vulnerable to storm surge are "woefully inadequate," according to a not-for-profit insurance industry study group.

The Tampa, Fla.-based Institute for Business & Home Safety (IBHS) based its findings on a study of property damage caused by Hurricane Ike, which struck the Bolivar Peninsula near Galveston, Texas, on Sept. 13, 2008.

IBHS' 60-page report found that significantly more Gulf Coast homes and businesses are imperiled by flooding from storm surge than previously recognized by property owners or policymakers.

"Lessons learned from Hurricane Ike, which is the third-costliest hurricane on record, should be used by vulnerable communities from Texas to Maine to effectively reduce property damage in all hurricane-exposed areas," said IBHS President and Chief Executive Officer Julie Rochman.

She noted that the study found "many properties are not built high enough to withstand storm surges, tightly enough to prevent water from causing interior damage, or strongly enough to prevent damage when high winds strike."

The IBHS report urges the National Flood Insurance Program (NFIP) to provide greater incentives for building well above the minimum elevations now in place, noting that more than 50 percent of the nation's population lives within 50 miles of the coast, with more than $9 trillion of insured coastal property vulnerable to hurricanes.

The NFIP, which is the federal government program that provides flood insurance to homes and businesses, also establishes base flood elevation (BFE) levels for properties.

According to the study's findings, the elevation requirement for homes on Texas' Bolivar Peninsula ranged between 13 feet for homes built in the 1970s and 17-to-19 feet for homes built beginning in 1983.

All but a handful of properties within the first few rows of houses from the coast, built to even the highest elevation requirements, were washed away during Hurricane Ike, the IBHS said.

However, 10 homes on the Bolivar Peninsula designed and built under IBHS' building code-plus new construction trademarked program, "Fortified...for safer living," survived the storm sustaining minor damage.

IBHS explained that the fortified homes had outdoor decks at 18 feet that were destroyed, but the homes, which were elevated to 26 feet, survived.

According to IBHS Senior Vice President of Research and Chief Engineer Tim Reinhold, most homes in coastal areas are built to or slightly above 100-year base flood elevations.

"A 100-year flood means that the level of flood water has a 1 percent chance of being equaled or exceeded in any single year. However, it is well recognized in the engineering community that coastal homes built to this level have a 26 percent chance of being flooded or demolished over the life of a 30-year mortgage. This chance increases to about 40 percent in a 50-year period," Mr. Reinhold said.

"All it takes is a breaking wave about 2 feet above the base of a house to knock out the bottom floor or destroy a frame house," he explained.

"The chances of destruction can be significantly reduced by employing what has been learned about the importance of proper elevation, which can be relatively inexpensive when building a coastal home," he continued. "For example, building to a 500-year base flood elevation reduces the chance of storm surge exceeding the base elevation to about 10 percent in a 50-year period."

Other items in the report include:

o A performance evaluation of superior construction techniques when tested by a truly extreme weather event.

o An outline of a course for rigorous laboratory testing to explore and resolve remaining issues with specific building materials and systems.

o Descriptions of the leading edge of construction and real estate markets, i.e., developers choosing to design buildings to the highest standard, because they understand the favorable cost/benefit ratio and want to meet consumer demand for safety and durability.

"Beyond the actual findings, our report includes a very practical, easy-to-follow retrofit guide for Texans in coastal areas to use. The guide takes into account the current Texas building code requirements and outlines specific retrofit options that homeowners and residents can use to harden their property by doing things such as strengthening their roofs," Ms. Rochman said.

The study, "Hurricane Ike: Nature's Force vs. Structural Strength," is online at http://www.disastersafety.org/resource/resmgr/pdfs/hurricane_ike.pdf.