SOUTH BEND — A rash of brass thefts on South Bend's southeast side has police, neighbors and businesses on high alert. Thieves have stolen an estimated 100 brass back flow valves over the past 10 days. Replacing the valves is necessary and expensive.

The main targets are home and business owners. Investigators estimate scrappers are getting about $12 per piece of brass.

But a few bucks for thieves adds up to major repairs for the victims.

"For us to come in and physically install it, you're probably going to be in the $240 range," said Wissco Irrigation General Manager Brian Davey.

A pressure back flow valve is used in irrigation or outdoor sprinkler systems. It forces the water to flow outward. But if the valve isn't there, the water gets sucked back in. Something like a water main break would likely contaminate your drinking water.

Davey told WSBT News there aren't many ways homeowners can protect themselves.

"About the only way I would know to protect yourself is to physically go out and remove the device yourself," he said. "Take it inside your house where it's secure and then re-install it in the spring."

You can also install a different kind of back flow valve on your irrigation system. The PVC piping is on the outside of the building, the brass part is hidden under ground. The problem: all the extra plumbing and the piece itself cost about $800.

But some homes and businesses have been hit more than once. Kerry Palmer with Palmer Funeral Homes said spending a little extra money the first time would have saved him in the long run.

"You figure, I've had 2 of those stolen," he said. "So I've got $600 to $700 wrapped up in the system already."

As they try to spread the word and protect more potential victims, police have a warning for the thieves.

"We're looking for you," said South Bend Lt. Scott Hanley. "We will find you and you will be prosecuted."

Another interesting part of this latest scrapping ring -- police say they haven't found back flow valves at local scrap yards. That means thieves are taking the brass elsewhere to get the money for it.

Investigators also believe the number of stolen valves could actually be much larger. Lt. Hanley told WSBT only a few of the victims have filed police reports. In many instances, he said they're calling repair companies and warning neighbors.

Hanley said even if you've already had a back flow valve replaced after a theft, it's not too late to file a police report.