Public water sources in the United States are required to be tested at least annually for a number of different contaminants, but the same rules don't necessarily apply to private water wells. Regardless, it is still a good idea to test your water at least annually in order to make sure your water is as safe as if you were getting it from a public source.

What You're Testing For

Water quality testing can cover a huge variety of water contaminants and conditions, so it really comes down to how thoroughly you want to test your water. Basic tests include those for pH and bacteria. For a more in-depth look at what's in your water, you can try collecting water samples to look for things like PCBs and radon. If you want to check your water for more than just bacteria and pH, then you may need to look for a specialized analytical lab, but these concerns aren't too uncommon and you shouldn't have much trouble finding a lab to perform these tests.

How to Go About It

Testing your water is very simple, and the hard work can be done by a local analytical laboratory. You can find a list of analytical labs that are accredited by your state's department of public health website. Once you find one that is nearby, go on their website and see which analytical services they perform, and what their going rate is. Labs will often charge per analyte. In other words, you will most likely pay more for a more thorough analysis that looks at a broader range of chemicals, bacteria, or other contaminants.

Once you've found a lab that suits your needs, check their requirements for samples. These labs will often send you a vessel in which to collect your water sample and require you to fill this vessel and then mail it to them or deliver it by hand. Four ounces of water in a bottle or a jar is a common volume and way to submit a sample.

Taking a Sample

In order to collect your sample, the lab you've chosen will likely provide you with a sampling protocol. If they don't, the process is very straightforward. Simply run your water pump for a few minutes, then place the jar or bottle under the stream of water while it is running, much like during a urine test at the doctor's office. It is often important to make sure that no air is in the bottle or jar, since this could cause contaminants to evaporate and be lost from the sample.

Creating a meniscus on top of the bottle or jar and then closing the lid is an effective way of avoiding an air bubble. To do this, simply fill the jar or bottle so that the surface of the water extends a tiny bit past the top of the glass or plastic so that the water's surface almost looks like a bubble atop the jar's opening. You'll have to fill your jar fairly slowly to achieve a proper meniscus, since filling it too quickly will cause your meniscus to break and spill, defeating the purpose of the meniscus. 

If you're looking to have your well water tested, read more about it online or follow the steps above.