A summer enjoyment for wife and I is regular forays to Weko Beach at Lake Michigan for a hot dog lunch, some sun induced vitamin D and a swim.

I don’t even bother to check out the poster on their bulletin board stating the last time the beach was checked for bacteria and deemed safe. That only makes me think about just what really is in that water.

It’s a family beach with lots of kids and the bathrooms up at the pavilion are a bit of a hike. Undoubtedly the water gets a touch salty on occasion. I’ve never seen any bobbing Tootsie Rolls, but…? And then there are those sea gulls that simply refuse potty training, the occasional salmon or sea gull carcass and so on.

I guess it’s some comfort that the EPA requires all public beaches to regularly check the water for E. coli bacteria. E. coli comes from any type of fecal matter and is present in small amounts virtually everywhere. The strain commonly found at beaches isn’t particularly nasty but at high levels can produce moderate sickness. High amounts of E. coli may also indicate its nastier buddies like salmonella and other mean bacteria, protozoa and viruses may be skulking around, too.

It’s a common notion that E. coli and the others are washing up onto the beaches from pollution by lakeshore development, improper sewage treatment, the aforementioned swimmers and decaying carcasses. That’s true but only part of the story. E. coli occurs throughout the whole beach area, not just at water’s edge. Typically, the most E. coli is found in the upper beach away from the water. Lesser amounts are in the submerged sand just off the beach and even less yet suspended in the water. E. coli diminishes the deeper the water gets. All this leads many experts to believe it’s the sand polluting the water, not the water polluting the sand.

Outbreaks of E. coli in the water often occur after wind driven waves stir the shallow bottom sand and wash higher onto the beach, releasing stored bacteria. However, the water born bacteria soon dissipates and amounts return to safe levels. Not so up on the beach. E. coli in beach sand is tenacious stuff.  It is self sustaining. Studies have shown it can actually winter over in the sand and then increase dramatically on its own during the warm summer months.  Once it has a hold in the sand it doesn’t need any new sea gull poo or other introductions for an outbreak to occur.

Chicago once attempted to clean a badly infected beach by removing six inches of sand from the entire beach and replacing it with bacteria free inland sand. That was a futile effort. The E. coli quickly colonized the new sand, returning to its original level within just two weeks. Most public beaches routinely clean the sand, sifting out cigarette butts, fried chicken, diapers and creature corpses. While that eliminates potential new bacteria sources it also stirs up and exposes the existing bacteria, making it much happier.

The cause of these outbreaks is not always clear. No direct correlation has been found with the amount of people on the beach. There is a relationship between the concentration of sea gulls and the level of E. coli in the sand but it would take an awful lot of bird bombs to be a significant factor. The beaches most often experiencing outbreaks are in urban areas and many suspect the vast networks of storm and sewer drains overflowing from heavy rain is often the culprit.

Whatever the cause, I don’t get why beach E. coli tests are taken from the water when the highest amounts are up in the sand. Maybe they figure you’re more likely to ingest water than eat sand. If that’s the theory they haven’t watched all those toddlers with their plastic shovels and buckets rearranging the entire beach while eating Pringles.  More likely, if we knew how many nasties are in the sand we’d freak out and drain the lakes. Ah, ignorance is bliss and I’m still eating Weko dogs.

Carpe diem.

Larry Lyons writes a weekly outdoor column for Leader Publications.

He can be reached at larrylyons@verizon.net.