High water levels are still posing a threat in South Carolina,and the situation is expected to worsen as rivers continue to rise,according to catastrophe modeling firm AIR Worldwide. Additional rain is expected to affectsome areas over the weekend.

The floodwaters continue to rise due to excess runoff as thesaturated ground cannot absorb more water. The ground hadalready been saturated from previous storms that affected the areain September, which prevented much of the water from the Octoberrains from being absorbed into the ground.

Several dams have failed affecting water supplies and worseningthe flood threat to several communities. One dam was breachedintentionally to alleviate pressure. Similar to many earthen damsand levees in the United States, some of these dams are susceptibleto weakening from rainfall.

Disaster declarations still in effect

A disaster declaration is in effect for several counties, andmany coastal areas, such as Georgetown,are bracing for the situation to worsen. Evacuations were under wayin several areas threatened by rising rivers or dam breaches.

As of October 8, Interstate 95 was closed between Exits 119 to132 and approximately 250 roads and 100 bridges remained closed. InLee County, afailed dam flooded a 30-acre pond, which washed out a road.

Farmlands have been severely affected and many crops haveincurred damage, particularly soybean, peanut, and cotton.

Potable water shortages

Potable water shortages were reported in Columbia and onOctober 8, Palmetto Health Richland shut off its watersupply to use a new source of water. The city’s largest hospital isresorting to alternative water sources. A temporary dam was put inplace while the Columbia Canal is being repaired. Most of Columbiais still under a boil water advisory.

According to the National Oceanic and Atmospheric Administration(NOAA), the one-day rainfall records for October were broken in atleast nine cities, with six of them breaking the one-day record forany month. Based on their analysis, AIR found that out of 73 gaugestations in South Carolina, six had flows with return periods of 20to 50 years, three had flows with return periods of 50 to 100years, two had flows with return periods of 100 to 500 years, andone had a return period flow that exceeded 500 years.