News-Herald Staff Writer

UHRICHSVILLE – Boaters, swimmers and fishermen enjoying the water this summer should be mindful of one restricted area in Tappan Lake.

A section in the outlet works area at Uhrichsville will likely remain closed until fall amid potential emissions of hydrogen sulfide gas, also known as H2S. It forms when the concentrations of sulfates in the watershed immediately behind the dams are higher than normal. During the summer months, the sulfates are converted to H2S gas through microbial activity occurring in the bottom layers of the lake. As the water leaves the lake, the hydrogen sulfide gas is released into the air, creating an unhealthy situation in the tailwater areas. H2S is recognized by its pungent, rotten egg-like odor and symptoms of exposure to high levels of H2S include fatigue, dizziness, nausea and headaches. Young children are at particular risk.

The Huntington, W.Va., District of the U.S. Army Corps of Engineers stated the gas is confined to the area adjacent to the outlet works only and does not pose a problem to recreational users of the lakes. There is no indication that fish taken from these lakes pose a health risk if consumed.

Tom Leach, assistant operations manager for the Muskingum Area of the Army Corps of Engineers, said the closure was only a precaution and officials will continue to monitor gas levels.

“We normally close it at this time of year and the hydrogen sulfide will stick around all summer. We won’t reopen it until September,” Leach said. “(Areas of) Clendening and Tappan Lakes are usually closed when they reach their threshold. It’s happened every summer since 2003 and is caused by microactivity from algae falling to the bottom of the lake. It falls into a dead zone where there is no oxygen. When we run it through siphons the algae becomes oxygenated and creates the gas.

Leach said it is a natural occurrence but the gas could create some health issues, but the restricted access would help reduce the risks.

“It’s a warning to let people know there’s potential for them to get nausea and dizziness.”

Due to public safety, the area immediately adjacent to the discharges at Tappan Lake have been closed and will remain so until the problem naturally corrects itself.

Darrin Lautenschleger, public information officer for the Muskingum Watershed Conservancy District, said incidents have occurred before.

“The Army Corps of Engineers has closed off areas at various times of the year when the hydrogen sulfide is up and closed access to the dam,” said Lautenschleger. “It makes sense because it’s been so warm here as of late.”

Corps personnel will continue to monitor the situation and will notify appropriate agencies as well as the public if concentration levels are determined to pose a threat to public safety.

For more information, contact the Muskingum Area Office at 330-343-

3613 or the Public Affairs Office at 304-399-5353.