Floodplain maps source of lawsuit

The state Environmental Protection Division has filed a lawsuit against a company that created floodplain maps along the Chattahoochee River, saying AECOM Technical Services “acted in bad faith” in creating maps that overestimated areas where flooding was likely.

The maps went into effect in April 2017, and the alleged errors could result in building restrictions or increased insurance costs for properties within the floodplain. Property owners would have been required to purchase flood insurance if the maps identified them facing a new risk of flooding.

It’s unclear how many properties may have been affected by the alleged errors, but the maps in question cover about 90 miles of the Chattahoochee from the south part of Carroll County down to Columbus. The complaint says the maps were demonstrably off and mistakenly raised the floodplain by 1.5 to 2.4 feet.

“When you’re dealing with a one-foot rise in the base elevation, pricing can be outlandish,” said Rod Hall of Hall Flood Plain Services. “One foot can swing the price $1,800, $2,300 (annually). ...These prices can just be staggering.”

The EPD filed the suit Friday in Fulton County Superior Court. In 2012, the state signed a $2.6 million contract with California-based AECOM for engineering services on the Chattahoochee and the Ocmulgee rivers. On the Chattahoochee, the contract was to create new floodplain maps, a process which happens periodically to ensure maps are up to date. The maps are used to assess a property’s risk of flooding, identify which properties must purchase flood insurance and set insurance rates.

In the complaint, the state said AECOM breached its contract and was negligent in creating maps that contained several obvious and material errors. No one from AECOM responded to request for comment on the allegation.

Jason Christian, a professional engineer used as an expert in the case, said in an affidavit that the floodplain applied in the maps represent “a significant error.” In one case, engineers failed to correctly apply the water flow coming from streams and tributaries that enter the Chattahoochee, the suit alleged.