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SolarBees go rogue on Jordan Lake
Winter storms have interfered with a million-dollar experiment on Jordan Lake, dragging several floating SolarBee pumps from their anchor points and bringing one into open water beyond the project zone.
The General Assembly had the fleet of 36 units placed in the region’s largest reservoir in July, hoping that they might stir away the algae that has long plagued it. Critics of the experimental project called the project a superficial replacement for the Jordan Lake Rules, a regulatory program that would have tried to limit the nutrient pollution that feeds algae overgrowth.
Opponents also asked at the time whether the circulators would be a danger to boaters.
In all, eight units drifted astray between November and January, likely due to high winds and high water, according to the Department of Environment and Natural Resources.
One of the 850-pound units lifted from the lake bed and went rogue, floating down the Haw River arm and out into the huge open expanse of the main lake. Others traveled from a few hundred feet to a quarter mile.
Ginger Travis was out in her wooden kayak about two weeks ago, checking on an eagle nest, when she spotted an odd angular mass in the Morgan Creek inlet.
“It was two SolarBees lashed together end-to-end with a very stout rope,” she said. As she got closer, she noticed that the underwater drives weren’t mixing the water, which is how the units are supposed to work their cyano-bacteria-killing magic.
“They’ve been tied together, and they’re not doing anything,” she said.
The units she spotted had remained inside the project’s boundaries, which include the Morgan Creek and Haw River arms. In the cases of those seven smaller moves, it seems that the units lost their grip in the muck, dragging their concrete anchors along with them. One of these units moved a quarter-mile in the Haw River inlet, according to DENR.
“That just happens when there are high waters and storms – there was no damage to any units,” said Ken Hudnell, a vice president and scientist for the manufacturer, Medora Corp., who was crucial in pushing the project through the legislature last summer.
In the most serious case of the nomadic water vacuums, however, a mechanical failure set a unit loose for an unusually long journey. A swivel mechanism, meant to let the unit orbit its anchor, instead jammed up, tangling the anchor chain and eventually ripping the mooring out of the lake bed, according to Emil Amheluk, customer service manager for Medora.
They received early reports that the SolarBee was drifting slowly in the inlet, but it’s unclear how long the unit floated on the lake’s open waters, where motorboats speed to and fro in warmer months.
“How long it was out there, I don’t know,” Amheluk said.
Hudnell says the first reports of the unit in the open water came in December. But Sarah Young, a spokeswoman for DENR, said the state learned of the escape on Jan. 17 and “immediately” had it towed out of navigation paths. Other units were seen drifting as early as November, according to Young.
The errant stirrers remained out of place for several weeks more, though. A Medora crew came in the last week of January to tow the units back to their positions and restart them.
In the meantime, the most successful escapee seemed to attract fish and clusters of fishing boats alike, Hudnell said.
The malfunctioning units needed to be adjusted to “best compensate for water depth, changing flow conditions, and high wind conditions ...” Young wrote. The cost of the fix was covered under the state’s warranty with Medora.
Molly Diggins, state director for the Sierra Club, said the incidents reinforced long-running criticism of the program.
“Now it also plays into the safety question – whether there won’t be future SolarBees that go missing,” she said.
Hudnell, the Medora vice president, said the rogue SolarBees were just part of the process.
“It potentially could be (a concern),” he said. “But we think we solved the problem now.”
The U.S. Army Corps of Engineers, which reviewed various concerns about the project and stamped its approval last year, didn’t immediately respond to questions about the loose units.
The temporary loss of a quarter of the pilot program units won’t prolong the experiment or otherwise limit DENR and Medora’s ability to draw conclusions on its effectiveness, Hudnell said. Winter months see relatively few dips in water quality, he said.
“It’s not a period of the year when you really have a need for much data,” he said. The data so far does seem promising, he said.
Ginger Travis, the kayaker, is still waiting on progress.
“There are times when it hasn’t rained for a long time, that the water clears enough that … you can see the bottom, 3 feet below. But that’s not very often,” she said.
“After it rains, up in the ends of the lake, the waters are almost opaque.”
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