By David Fleshler, Sun Sentinel (October 20, 2011)
A sea-level rise of just a few inches will bring flooding to South Florida cities, contaminate sources of drinking water and lead to sharp increases in utility bills over the next 20 or 30 years, according a study released Wednesday by Florida Atlantic University.
The study found that projected sea level increases of 3 to 6 inches by 2030, due to global warming, could overwhelm flood-control systems that in many areas are more than 50 years old. The authors provided a list of steps to be taken in the coming decades, from moving drinking-water wells inland to installing more pump stations, that could help the region cope with the higher water.
"Unprecedented sea level rise and other climate change impacts are likely to result in serious threats to the water supply, increased risks of flooding, hurricane damage, huge infrastructure investments and other consequences both known and unknown at this time," states the study, conducted by researchers at the university's Charles E. Schmidt College of Science and College of Engineering and Computer Science.
Global warming causes sea levels to rise because water expands as it increases in temperature and because glaciers melt. In the past century, sea levels have risen 4.8 to 8.8 inches, largely due to global warming, according to the Environmental Protection Agency.
Higher sea levels will increase the intrusion of saltwater into underground sources of drinking water, forcing cities to abandon wells near the ocean and drill new ones, according to the report.
As a case study, the report used Pompano Beach, where the city is fighting — so far successfully — to keep saltwater intrusion from its eastern wellfield. Although most of the city stands on relatively high ground, low-level coastal areas would be inundated.
By 2030 the city will have to spend millions to upgrade water plant equipment, install pump stations in low-lying areas and upgrade its sewer system, passing the cost onto its customers, according to the report.
"Sea level is creeping up on us," said Barry Heimlich, a researcher at FAU, who led the study. "And in a few decades it could overwhelm our storm drainage system."
Randy Brown, Pompano's utilities director, said the study was basically accurate and the city was incorporating the need to accommodate sea-level rise into its various water plans. He said it would be impossible to estimate the impact on bills over the next 20 years. Although he's optimistic about protecting drinking water supplies, he's unsure whether the city will be able to prevent flooding of low-lying areas.
Frederick Bloetscher, associate professor in the FAU Department of Civil, Environmental and Geomatics Engineering, says flooding during storms in eastern sections of South Florida cities provides the average citizen with the most powerful evidence for the reality of global warming.
"Ask people if anything's different," he said. "Ask them if their streets flood more. You do see more flooding when it rains, and people can relate to that. People's perceptions that things are different on the ground are right. It is reality."
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