Tom Eisele said he moved to a lakefront home in Tega Cay seven months ago because he loves the water, but now, he's worried about what's in it.
"The toilet paper comes out and goes onto the ground then directly into the lake," he said.
After a heavy rain in February, Eisele said a manhole located just feet from the shore spewed human waste into Lake Wylie.
SLIDESHOW: Lakefront Residents Concerned About Sewage Overflows
"Toilet paper comes out, tampons, feces," he said.
Neighbor Linda Stevenson said she is also troubled.
"This is a major concern, because my grandchildren swim out here," Stevenson said.
Contact with sewage can cause gastro-intestinal problems or infections.
Stevenson said she can recall six other overflows in her 15 years living on the lake.
Stevenson and Eisele worry the aging sewer system, which is made of older terra cotta piping, could be failing.
It's operated by a private company called Tega Cay Water Service, which is based in Columbia, S.C. The company serves a few hundred homes in the original development, which neighbors call "old Tega Cay."
However, a supervisor with Tega Cay Water Services said debris in the line and failed pumps at a lift station caused the spill, not old pipes.
He said they have corrected those problems and have no plans to replace any older pipes.
Catawba River keeper David Merryman said he thinks overflows in old Tega Cay are a problem.
"Specifically for Lake Wylie, they are a drastic concern," he said. "In old Tega Cay, they have had a history of sanitary sewage overflows that end up directly impacting and entering Lake Wylie."
The South Carolina Department of Health and Environmental Control said Tega Cay Water Service reported 12 overflows since the start of 2009, spilling a total of 45,800 gallons of raw sewage.
Merryman is pushing for a better system to inform the public when overflows happen.
"We have some very aging infrastructure, and as that lake has developed drastically over the past few decades [so] that infrastructure hasn't been able to keep up," Merryman said.
Tega Cay Water Service is currently petitioning the state for a rate increase, which angers Eisele, who wants major improvements made.
"We don't know if the problem is fixed until the next heavy rain storm," he said.
The Department of Health and Environmental Control is Monday at 6:30 p.m. in Tega Cay City Hall.