With reports of leaking landfills, drainage from abandoned mines and crumbling gasoline storage tanks tainting Utah water supplies, it doesn't take much convincing when somebody comes around offering to test your drinking water.

Be wary of such offers, a Utah State University water quality specialist said.Not all companies offering water tests are legitimate. They often have more in mind than just testing your water; they want to sell you water treatment devices, said Kitt Farrell-Poe, USU extension environmental engineer.

"My concern is about water tests performed by salespeople that supposedly reveal certain contaminants," she said. "I'm worried that those test results are not really accurate."

To protect yourself, Farrell-Poe said it is wise to take the test results from a salesman and have them independently verified by a state certified water testing lab.

Not only can it legally protect you, since a court will only recognize the results from a state certified lab, it can also save you money. By knowing what particulates need to be removed, you avoid buying more water purifying equipment than necessary.

For example, if you only have a problem with hard water, she said you don't need an activated carbon unit. While such a unit removes certain organics, taste, odor and color in water, it will do nothing to remove hardness. The same goes with a more expensive reverse osmosis device that can cost up to $1,500. Such a device should only be used if you have serious contaminant problems.

Farrell-Poe said if you have any doubts about the quality of your water, it's worth getting it tested, especially if you're connected to a private water source - but avoid "free" home water tests.

If you are on a municipal water system, you have the right to ask to see your city's water test results. Law requires that municipal water systems be regularly analyzed for different constituents, she said.

Bear in mind, however, that bacterial problems not found at the point of distribution may show up at your tap. She said there could be pathogens built up in your aerator, for instance, or a break in the line that may allow bacterial access at other points.

"There is a difference at the tap versus at the point of distribution," she said.

If you have only aesthetic concerns about your water, such as hardness, she said it is not necessary to have your water tested by a certified lab. You can purchase water hardness test kits at most home improvement retail stores or take a sample of water to a municipal swimming pool where testing equipment is available.

For more information on the nearest state certified water labs available, call your county health department or USU county extension agent.