Some homeowners in Beaufort County might pay 25 percent more to insure their homes this year, now that new national flood insurance policies have taken effect.

Under the Flood Insurance Reform Act of 2012, flood insurance premiums will no longer be subsidized for second homes built in high-risk flood zones. The law applies to homes in South Carolina built before Sept. 30, 1977, or those built to standards that are now outdated, according to the Federal Emergency Management Agency.

Those homes previously were allowed to receive discounted rates, but no longer.

The new law is designed to prevent the subsidized flood-insurance program from further financial bleeding. The subsidized rates will be phased out through premium increases of 25 percent a year, starting this year.

Second-home owners will see the new rates when their flood insurance policies come up for renewal, said Nick Hunt, an insurance agent at Lowcountry Insurance Services on St. Helena Island.

He said the law has had "very little impact" so far, but he expects to hear many complaints about the changes by summer, when most flood policies come up for renewal.

"June, July and August -- there will be a lot of people crying when they see their premiums," he said.

In addition to policy renewals, the new rates can be triggered if:

The property is sold.

Flood insurance coverage on the property lapses and the owner seeks to renew the policy.

A property's market value rises by more than 30 percent because of renovations or additions.

A property incurs damage of more than half of its market value.

Later this year, the increases also will hit business properties, according to Janice Mitchell, a FEMA insurance specialist who covers South Carolina. She said the agency has not determined when those rates would be effective.

Realtors, insurance agents and local flood-plain administrators have been meeting to discuss the changes and determine how the area will be affected.

"It's a learning process right now," said Linda Frank, president of Sea Pines Real Estate.

At least half of Beaufort County is in a flood-hazard area and could be subject to the new rates, according to county flood plain manager Hakim Bayyoud.

Property owners can keep their rates from increasing unnecessarily if they can prove the elevation of their property is higher than flood-plain maps indicate, said Joe Cecil, insurance examiner for the National Flood Insurance Program. Elevation certificates can be completed by licensed land surveyors, architects or engineers.

"Anybody who lives in or very near a flood-hazard area should consider getting an elevation certificate done sooner than later," Cecil said.

Bayyoud said premiums could change again for all property owners, not just second home owners. That's because elevation maps upon which flood-insurance rates are based are outdated and will be replaced by FEMA. The current maps were released in 1986 and partially updated in 1992.

The new maps could show some properties in areas of lower elevation, which would translate into higher rates. Others, however, could benefit if the maps show their properties in higher elevations.

The agency was supposed to release new maps by the beginning of this year but now they're now expected until 2014.

Follow reporter Brian Heffernan at twitter.com/IPBG_Brian.

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