COLUMBIA — The rainy summer has done more than breed mosquitoes and drench crops.
Months of downpours have refreshed the Floridan Aquifer.
If only just a little.
“The rains have had a noticeable effect,” said Scott Harder, a hydrologist for the S.C. Department of Natural Resources. “We are not seeing the typical drawdowns at many sites that occur during this time of year, and in some cases water levels are increasing.”
He said it’s likely attributed to of a combination of groundwater recharge and reduced irrigation and pumping from the Floridan.
For one thing, when it’s always raining, people aren’t as eager to water their lawns and golf courses.
The aquifer is a natural water bank made of limestone and dolomite, that serves as a primary source of water almost 10 million people. It extends 100,000 square miles beneath southern Alabama, southeastern Georgia, southern South Carolina and all of Florida.
But Harder and other experts agree any extra water won’t do anything to relieve the effects of saltwater intrusion, which threatens the water supply most immediately in Hilton Head Island and parts of greater Bluffton.
“While the abundant rainfall has helped to recharge all of our groundwater systems, the upper Floridan is a deeper aquifer, and it would take many years for this recent rainfall to reach the aquifer beneath Hilton Head Island,” said David Baize, assistant chief of S.C. Department of Health and Environmental Control’s Bureau of Water.
“Saltwater is entering the upper Floridan aquifer due to pumping of the groundwater from wells, and no amount of natural recharge would be able to stop the saltwater intrusion caused from this pumping.”
For the area’s water supplier, the Beaufort-Jasper Water and Sewer Authority, the heavy rainfall brought a special odor and color to the water, at least temporarily, because organic material was swept into the Savannah River. It has since been fixed.
Still, BJWSA spokesman Matthew Brady pointed to the good side of the wet conditions.
“Lakes Hartwell, Russell and Thurmond have fully recovered from the drought and are full,” he said. “This is good news, but releases from the lakes increased significantly in July due to the continuing rain.”
This led to flooding in the lower Savannah River basin.
“This was a pretty historic event, in that we had not seen this much flooding in the Savannah in decades,” he said.
Heavy rains that flood the area have lots of healthy environmental effects, said William Conner, a professor and assistant director of the Baruch Institute of Coastal Ecology & Forest Science.
“Flooding has both good and bad effects on the environment,” he said.
“Floods help move sediments and nutrients around, thus rejuvenating the fertility of the soils... and helping to build up the surface elevation.”
That’s important in coastal areas, said Conner, because, “we are seeing the impact of sea level rise and saltwater intrusion into our fresh water marshes and swamps. The deposition of sediments helps offset the rise in sea level, thus maintaining the marshes.”
Other benefits, according to Conner: “Flooding can actually trigger breeding events, migration, and dispersal of aquatic organisms.”
Another happy outcome? More fish.
“Freshwater floods can lead to higher fish production in our coastal estuaries as many coastal resources are dependent on nutrients supplied from upstream lands,” said Conner.
HOW RAINY WAS IT?
Consider this: Savannah experienced its fifth wettest summer and third wettest year to date, according to data from the S.C. DNR. South Carolina, as a whole, experienced its wettest July since 1916.
• While Savannah shared in its eastern neighbor’s wet conditions, data show it was far from record-breaking. Savannah had an astonishing 20 inches in July of 1964, the “any-month” record since 1948, according to data from Wes Tyler, a climatologist for SC DNR. In July of this year, there were only about 12 inches.
• This year, a well in Yemassee reached a water level that was the highest it’s been since early 2006. That’s even more unusual to see right now, said Harder, because usually winter or spring is when wells hit annual peak levels.
• Farmers have suffered: It’s been a disaster because of the heavy rains. On Wednesday U.S. Secretary of Agriculture Tom Vilsack granted Gov. Nikki Haley’s request that 36 South Carolina counties be given a disaster designation. The decision also named six Georgia counties, including Burke, Chatham, and Effingham, as contiguous disaster areas. Farmers in all are eligible to apply for emergency federal loans. Of South Carolina’s 36 primary disaster counties, damage to wheat, soybean, peaches and other crops exceeding 30 percent.