FEMA Flood Maps Rapped

This is an article from the Cape Cod Times. Please disregard the political overtones as the technical flaws are more interesting.

The state congressional delegation has asked for a delay in implementing the new federal flood maps for Massachusetts after a scientific review raised questions about simplistic technology and flawed data.

The proposed changes to the flood risk maps could force thousands of Barnstable County homeowners to pay significantly more for federal flood insurance.

The delegation wrote to Federal Emergency Management Agency Administrator Craig Fugate on Friday asking for the delay, according to U.S. Rep. William Keating's office Friday. The delegation asked Fugate for a detailed reply by Feb. 1.

The request stems from findings indicating that FEMA used a methodology from the Pacific coast to create the maps for Massachusetts, according to a Dec. 3 memorandum to Keating from Brian Howes of the University of Massachusetts Dartmouth School for Marine Science and Technology and John Ramsey of Applied Coastal Research and Engineering Inc. in Mashpee.

A more sophisticated methodology that was used specifically for the mid-Atlantic states would be more appropriate for Massachusetts, the memo stated.

"They really didn't do some of the higher-level analysis," Ramsey said Saturday. That level of analysis could reduce the inland reach of the flood zones, he said.

Howes and Ramsey also noted another error first identified by a consultant for the town of Marshfield, where an older benchmark for water levels was used instead of a newer version. That error could lead to inaccuracies on the flood zone maps, the pair said in the memo.

To come to their conclusions, the pair reviewed research conducted for Marshfield as part of an appeal with FEMA of flood zone boundaries and used their general knowledge of FEMA's methodology for Massachusetts, Ramsey said. Neither of the researchers were paid for their work.

Keating said he became concerned about the FEMA maps after his constituents told him that escalating flood insurance premiums could force them out of their homes.

"If this is something that affects someone's ability to stay in their house, then it should be based on the most accurate science possible," he said. Keating said he wanted FEMA to "go back and do it right."

The new maps are intended to more accurately reflect an area's risk of flooding during a major storm, and are being revised nationwide.

On Cape Cod, the mapping changes have placed many property owners into a higher-risk flood zone for the first time. Homeowners with federally insured mortgages are required to purchase flood insurance if their properties are in high-risk zones, and those premiums can be expensive.

"I would say that is a very good start," Dennis homeowner Peter McDowell said Saturday of the request for a delay. "It's not just the delay that is big. It will put some pressure on (FEMA) to account for what they did."

McDowell was one of seven property owners in Dennis who successfully appealed their high-risk designation on the FEMA draft flood zone maps with the help of a land surveyor. The seven property owners learned of the success of their appeals earlier this month.

The annual premiums for flood insurance could have been $20,000 or higher, McDowell said. That kind of annual expense also negatively affects the potential sale price for a house, he said.

In their review, Howes and Ramsey said that for the 2013 maps for Marshfield, FEMA used a methodology to measure wave setup called the direct integration method), which was developed to address issues along the Pacific coast, according to their Dec. 3 memo. Wave setup is where water levels along a coastline are elevated because of breaking waves pushing water against the shore. The DIM methodology calculates a higher wave setup value than what would be calculated using a physics-based modeling tool.

FEMA used that type of more finely-tuned methodology for the coastlines of a mid-Atlantic FEMA region, the memo stated. That region encompasses Washington, D.C., Delaware, Maryland, Pennsylvania, Virginia and West Virginia. "Overall, the preliminary FEMA maps for the town of Marshfield ... provide overly conservative results, which consistently overpredict the level of flooding that would occur during a 100-year storm event," Ramsey and Howes wrote in their memo.