Rain Dumped by Hurricane Causes at Least 17 N.C. Dams to Fail

At least 17 dams in North Carolina burst from the rain dumped by Hurricane Matthew, most of them in the Cape Fear River Basin.

The News & Observer of Raleigh reports state inspectors knew where the rains could cause catastrophic failures. During Matthew, they were “babysitting” critical dams to be able to call for an evacuation if needed.

Dam Safety Program spokeswoman Bridget Munger says none of the 27 deaths in North Carolina attributed to Matthew was caused by a dam failure.

Most of the more than 3,200 dams statewide are earthen and privately owned.

The state’s 62 inspectors must inspect all high-hazard dams at least once every two years. Those are dams whose failures could cause death or costly property damage. Others can go decades without being inspected.

U.S. insured losses resulting from Hurricane Matthew have been estimated at between $1.5 and $5 billion, according to catastrophe risk management firm RMS. An estimated 70 percent of the U.S. loss is to residential lines, while storm surge-driven coastal flooding is estimated to contribute around 30 percent of the all-lines loss – including coverage leakage and an escalation in claims severity for wind-only policies in situations where wind and water hazards co-exist in residential lines of business.

The Southeast region of the U.S., specifically, Georgia, South Carolina and North Carolina sustained an estimated $1 billion to $3 billion in losses. Storm surge contributed to an estimated $200 million to $500 million in additional losses for the same region.