Vacationers to Myrtle Beach might want to think twice before diving in the ocean after a heavy rain.
June proved to be the wettest month since 1999 on Horry County beaches – and with a rainier-than-normal summer forecast, bacteria levels could soar in the surf.
Higher rainfall generally increases the threat of polluted stormwater washing off the land and stirring up sediment in waterways. That’s a real issue in the Myrtle Beach area, a big tourist destination with a stormwater problem.
Unlike other parts of the state’s coast, Grand Strand communities drain stormwater directly onto the seashore and into beach-flowing inlets. That’s believed to be why Myrtle Beach has more instances of high bacteria levels than other South Carolina beaches.
Those who track ocean water quality say the public should be aware of the potential threat.
While sun-starved vacationers are eager to swim in the ocean after the rain stops, experts said it’s best for people not to duck their heads under the water – particularly if they are near a storm drain or inlet – for at least a day.
“We’d recommend avoiding swimming 24 hours after a rain and 72 hours after a heavy rain,” said Jon Devine, who tracks beach water quality for the Natural Resources Defense Council. “It is not uncommon for stormwater pipes to go right to the beach.”
So far this summer, about 9.5 percent of the surf samples tested by state regulators on Horry County beaches exceeded a federal standard for safe swimming, according to the S.C. Department of Health and Environmental Control’s website.
The hot spots were in an area from Surfside Beach to northern Myrtle Beach, the state’s top tourist attraction. DHEC reported Tuesday that 17 percent of the samples this year in the city of Myrtle Beach exceeded the limit, which was higher than other beaches. Samples collected this May and June ranged from just above the federal enterococcus bacteria limit to more than 50 times that standard, according to DHEC’s website.
So far this year, the percentage of elevated levels appears to be lower than what the NRDC found in a 2012 annual ocean water quality report – and one official in North Myrtle Beach said the city hasn’t found that June’s increased rain has affected water quality.
But the summer is far from over. The NRDC’s study, released last week, included data from all of 2012 – including August 2012, the rainiest August in the previous five years. Nationally, only four of the 30 states examined by the NRDC had higher percentages of samples exceeding the safe swimming standard than South Carolina.
DHEC’s current numbers are from May 15, when the beach season began, through the end of June. Rainier-than-usual weather is forecast for the rest of the summer, according to the state Climatology Office.
Sally Knowles, a former DHEC regulator who helped launch the state’s ocean-water testing program, said beachgoers need to be aware of the relationship between rainfall and tainted surf.
“I would not hesitate to wade or walk in the surf, but I would be reluctant to go under the water” after rainfall has soaked the beach, Knowles said. “That is where the issues come in. If you swallow water that is potentially contaminated or it gets in your ears or nose, you can have issues.”
People who ingest polluted ocean water run a greater risk of getting colds or upset stomachs, research has shown. Pathogens can be found in contaminants that wash into the ocean. Common pollutants in runoff include animal droppings, oils, fertilizers and sewage, which can come from leaking septic tanks or sewer pipes. Some vacationers to Horry County beaches have in the past complained of illness after swimming, but few if any studies can confirm that.
Rainfall data show that 2012 was not nearly as wet as 2013 is turning out to be.
More than 12.4 inches of rain fell on the northern Grand Strand last month, compared to 2.5 inches in June 2012, according to National Weather Service data. Rainfall in Horry County is about twice the amount that fell in the Columbia area in June, weather data show.
Hope Mizzell, climatologist with the S.C. Department of Natural Resources, said June 2013 is the wettest June in parts of Horry County in 14 years. An extended pattern of moist tropical air has kept things soggy in South Carolina so far this summer, although the weather is expected to clear some by this weekend.
Spokespeople for the cities of Myrtle Beach and North Myrtle Beach downplayed concerns about water quality.
They said the time when bacteria levels go up the most is when it rains after an extended dry period. Bacteria and other contaminants that have built up on roofs, streets and lawns are more concentrated and, thus, more of a threat, they said.
After that initial flush, contamination levels aren’t a concern, said Mark Kruea, a spokesman for the city of Myrtle Beach.
“Water quality, with lots of rain, is generally pretty good,” Kruea said. “If you get lots of rain after a long dry spell, that’s where you might have an issue.”
But scientist Fred Holland, a former director of the federal government’s Hollings Marine Laboratory in Charleston, said extended rainy weather generally continues to send contaminants into waterways.
“The first flush is an important flush, especially after a dry period,” said Holland, who has studied stormwater extensively. “But that doesn’t mean that after the first flush, all of the pollution has been washed in and it is over. There is a continual, lower concentration of stuff being washed in.”
DHEC spokesman Jim Beasley said his agency has not issued any advisories against swimming on South Carolina beaches this year. He did not say why, but did note that DHEC has 28 sites where permanent signs are on storm drains and near tidal creeks to warn against swimming there, particularly after heavy rains.
Not a recent issue
The Grand Strand’s practice of running drainage onto beaches has been questioned since the 1970s. DHEC did not test ocean water quality regularly until The State wrote a series of stories in 1996 outlining the pollution problems that exist near ocean-flowing drainage pipes.
Since then, DHEC and Grand Strand cities have launched a beach monitoring program and Myrtle Beach area communities have worked steadily to eliminate the 150 drainage pipes that once flowed onto beaches.
Myrtle Beach and North Myrtle Beach report spending more than $60 million on drainage-related issues, mostly to pipe stormwater well past the surf where people swim.
Since efforts began more than a decade ago, the cities have removed about 30 percent of the 150 pipes from the beaches. Both cities plan projects this fall to add additional deep-water ocean outfalls – a move that should eliminate up to 17 more seaside drainage pipes, city officials said Tuesday.
“In 1996, when The State newspaper tested the water and ran that story, it hacked everybody off, but it opened a lot of eyes, too,” North Myrtle Beach spokesman Pat Dowling said.
“After pointing fingers back and forth, (cities) started getting serious about water quality.”
BEACH BY BEACH
Beaches where water samples exceeded standards for safe levels of bacteria in 2012 include:
Myrtle Beach State Park and campgrounds: 20 percent of samples exceeded standard
Surfside Beach: 19 percent
Myrtle Beach: 17 percent
North Myrtle Beach: 11 percent
Arcadia Beach: 9 percent
Briarcliffe Acres Beach: 9 percent
Harbor Island: 9 percent
Hilton Head Island: 6 percent
Hunting Island: 6 percent
Garden City Beach: 5 percent
Pawleys Island Beach: 4 percent
Edisto Island: 2 percent
Folly Beach: 2 percent
Fripp Island: 2 percent
THE TOP THREE
The three beaches where water samples most often exceeded safe standards for bacteria in 2012 include:
Myrtle Beach State Park
20 percent of samples exceeded standards