By Skip Rigney

My grandchildren live hundreds of miles from the nearest ocean. So when they visit us during the summer, we usually make an outing to the nearby white, sandy beaches. Most days there are plenty of quiet spots to choose from on the Mississippi coast. We like to wait until the late afternoon, giving the heat of the day a chance to subside. They build sand castles, pick up shells along the water’s edge, and chase seagulls and terns.

But, what about actually getting in the water? Sometimes bacteria concentrations along the beaches of the Mississippi Sound can get high enough to pose a safety concern.

Fortunately, the Mississippi Department of Environmental Quality (MDEQ) through its Beach Monitoring Program provides helpful information about the water quality at 21 locations along the beaches of Hancock, Harrison, and Jackson counties. Every week water samples are collected at these locations. The samples are sent to a laboratory for testing to determine the concentration of enterococcus sp. bacteria. Within 24 hours the test results are available and the information is updated on the program’s website, https://opcgis.deq.state.ms.us/beaches/.

Bacteria are always present in a thriving ecosystem like the Mississippi Sound. Most of them are irrelevant to us humans. However, enterococci are found in the digestive tracts of warm-blooded animals such as birds and mammals, including humans. Elevated concentrations of enterococcus sp. bacteria indicate an increased risk that other disease-causing bacteria and viruses may also be present.

When the concentration of enterococcus sp. exceeds the safety threshold, MDEQ issues an advisory for that section of beach, and the location is flagged on the website. While the advisory is in effect, MDEQ says it’s still OK to play on the sand, but strongly recommends no water contact. If you do decide to get wet, you’re “swimming at your own risk.”

The task force collects more samples for retesting in the days following the issuance of the advisory. When the concentration of enterococcus sp. falls back below the threshold of concern, the advisory is lifted and the location once again shows up as “green” on the website.

Two major causes of elevated bacteria levels are weather-related. Strong winds can stir up bottom sediments, and heavy rain increases runoff. With over 200 storm drains and other discharge points located along the Mississippi coast, that means plenty of potential for water contaminated by man-made sources making its way into the beach waters.

That’s why MDEQ has a standing recommendation that swimming not occur during or within 24 hours of a significant rainfall event, according to MDEQ’s Emily Cotton, who is the coordinator for the Beach Monitoring Program.

It has been abnormally wet across coastal Mississippi this summer, and that has reduced the number of safe days to play in the water along the Mississippi beaches. This past week we remained stuck in an area of relatively lower atmospheric pressure between higher pressure centered over the Atlantic and another high over the southwestern United States.

Until one of those highs extends further into the Gulf South, we will continue to have more than the average number of showers. The computer weather models hint that our pressures may at least briefly rise and shower coverage decrease by the middle or latter part of the upcoming week.