HOW COASTAL CHANGES AND DEVELOPMENT AMPLIFIED DAMAGE IN THE 1935 HURRICANE IN THE FLORIDA KEYS-LESSONS FOR THE FUTURE

On Labor Day in 1935, the most powerful hurricane in U.S. history destroyed the middle part of the Florida Keys. The exceptional damage and loss of life was a function of storm strength as well as the shoreline changes that had been made during the construction of the Florida East Coast Railroad to Key West. Tidal channels had been filled to make causeways and wider stretches of water had been spanned by stone piered bridges. This significantly reduced tidal exchange between the Atlantic and Gulf of Mexico. The railroad resulted in greater development and by 1935 hundreds of workers, mostly WW1 veterans, were engaged in building U.S.1 parallel to the railroad. The Weather Bureau predicted the Labor Day storm would pass south of Florida. Construction officials relied on the Weather Bureau forecast, but locals noted that the swell approach direction indicated a landfall in the Middle Keys and retreated to shelters. Officials were slow to realize the danger, and requested an evacuation train from Miami only on the day of landfall. The train was delayed and arrived in Islamorada at the height of the hurricane and was swept off the tracks by high water. The hurricane underwent spectacular intensification between the Bahamas and the Keys. The front eyewall of the storm pushed water over the reef toward the Keys, but passage into the Gulf of Mexico was slowed by the reduction in the tidal prism from railroad and highway construction. By the time the rear eyewall made a landfall, all but the highest railroad embankments were overwashed. As the hurricane passed, coastal waters were pushed seaward. However, high Gulf waters could not return rapidly into the Atlantic and backed up against the Keys. The resulting hydraulic head caused several of the railroad embankments to fail, sweeping many of the survivors to their deaths. Winds of over 155 miles per hour destroyed most of the stuctures that had resisted the storm surge. Over 600 people, most of them veterans, were killed and a Congressional Investigation followed. The Florida Keys are far more developed and populated today and building practices have modified the shoreline even more.today and evacuation is a nightmare because U.S. 1 has many stretches that are only 2 lanes wide. The landfall of a major hurricane here in the future would have catastrophic results. We must learn from the past.