Despite extensive media coverage of the widespread, multistate flooding caused by Superstorm Sandy last fall and Hurricane Irene in the summer of 2011, 1 in 5 homeowners is still surprised to learn that home insurance does not cover flooding, according to a Bankrate nationwide survey as part of the April Financial Security Index.

The survey found that 18 percent of consumers didn’t know that a standard homeowners policy specifically excludes flood-related damage, while 81 percent were aware of the need to purchase a separate flood insurance policy from the federal National Flood Insurance Program, or NFIP, to guard against flood loss.

The Federal Emergency Management Agency, or FEMA, which administers the NFIP, generally classifies properties as either at high risk or moderate-to-low risk of flooding. When consumers were asked if they knew for sure which category applies to their home, just more than half, or 51 percent, said “yes,” while 43 percent said “no.”

Bankrate’s survey was conducted by Princeton Survey Research Associates International and involved landline and cellphone interviews from April 4-7 with a nationally representative sample of 1,003 adults in the continental United States. The margin of error is plus or minus 3.7 percentage points.

“I was very happy that 4 out of 5 survey respondents understood that standard homeowners insurance does not cover flood,” he says. “This number is a much higher awareness level than we’ve seen in the past.”