We are required by our Bottom Barrier permit to inspect the barriers we have in place through the end of October each year. This year our final inspection took place on an unusually warm day in early November. The air was almost 60F. The water was much colder.
The purpose of the inspection is to find and fix what our permit calls “billowing.” The sheets of “fish grade polyvinyl chloride fabricated liner” are held down along their length by “weighting devices” that are epoxy coated pieces of steel “rebar.” For a variety of reasons gas can collect under the sheets. The most common cause is the decomposition of decaying milfoil. Our diver swims along over each sheet and removes any billowing, straightening the sheets and replacing the rebar weights as necessary.
LEON HANDS AJ TWO ADDITIONAL PIECES OF REBAR
AJ CARRYING REBAR UNDER WATER
Our bottom barriers are currently placed at bottom depths varying between about eight and fifteen feet. There are about 200 sheets, each 6 feet by 100 feet, covering about two acres. (the sheets overlap by about a third, if you are checking my math)
Here is AJ trying to warm up after a stretch under water. He said that although one can begin to get used to the cold, his fingers get numb after a while. Also he would want me to mention that our divers’ “dry” suits really aren’t.