Wichita ? Wichita water officials say they will find a way to keep zebra mussels from hurting the flow of water from Cheney Reservoir, which supplies the city’s water.

Adult zebra mussels were found Friday at the reservoir. The shelled mollusks have been known to clog intakes at water and power plants. They also out-compete native fish and mussels for food, and their sharp edges are a hazard to swimmers and waders.

While the mussels could pose a serious threat to Wichita’s water supply, city officials say they have been monitoring them for years.

The ones spotted so far haven’t colonized enough to impede the water flow, the city said. The invasive species can colonize in layers up to a foot thick; a female zebra mussel can produce more than a million young in a season.

The mussels move to new waters in boat ballasts and recreational craft by clinging to bait buckets and engines.

Wichita has approved a study that will try to find a permanent protection system at the intake that will either kill the mussels or prevent them from attaching to the pipe.

Angela Cato, spokeswoman for the city’s water utilities department, said there is no timeline for the study.

The first zebra mussels in Kansas were found at El Dorado Lake in 2003. Since then they have spread to Lake Afton, Winfield Lake, and Perry and Marion reservoirs.

The Kansas Department of Wildlife and Parks expects a population explosion that will cause problems in coming years.

Zebra mussels have caused billions of dollars in damage to utilities, docks and beaches since they arrived in the U.S. from Eurasia in the 1980s.