Drinking Water

It is recommended that drinking water wells be tested for coliform bacteria and nitrates annually or if a change in color, taste, or odor is discovered. Additionally water samples should be collected and analyzed for bacteria when any of the following occurs:

• any repair or work is performed on a water well or plumbing,
• a water softener or filter has been installed,
• an underground sprinkler system has been installed, or flooding has occurred near the well.

Bacteria and Nitrate testing is available through the Kalamazoo County HCS Laboratory, or through a number of certified drinking water laboratories. Check here for a list of certified drinking water labs, or contact us for additional information.

Sampling your drinking water supply

The following are ways that you can have your water well sampled:

1. The Kalamazoo County Environmental Health staff can sample your well for bacteria, nitrates or other compounds of your choosing. After submitting the Water Sample Request form (located in our Application Quick Links) to our office, you will be contacted to set up an appointment.
2. You may also sample the water well yourself. Special containers are needed for each water sample, and each lab uses different containers. Please review the guidelines below for good water sampling practice, but always follow any instructions that come with the sampling containers.
• Do not open the bottle until you are ready to collect the sample.
• Do not touch the inside of the cap or bottle.
• Do not rinse the bottles. Some bottles may contain preservatives that need to stay in the water sample.
• Select a clean indoor faucet, and run the cold water for about five minutes or two pump cycles. Reduce the water flow to a pencil-sized stream. Remove and hold the cap while you fill the bottle according to the instructions provided by the lab. Do not let the cap or bottle touch the faucet. Avoid splashing water.
• Replace and secure the cap to insure that the sample does not leak.
• Complete all known information on the form by printing or typing legibly. A separate form is required for each sample bottle.
• Refrigerate the sample until you are able to deliver it to the lab.
• Deliver the sample, on ice, with the appropriate form.

Understanding your drinking water results

Bacteriological Analysis

A bacteriological analysis of drinking water determines the presence of coliform bacteria. Coliform are found in the intestinal tract of warm-blooded animals, surface water, some soils, and decaying vegetation, and are used as "indicator" organisms. If coliform bacteria are present, pathogenic or disease causing organisms could be present. A detected (or positive) result may indicate that a water supply is not properly protected from contamination. The test also assesses the presence of E. coli. If E. coli is detected, it is more likely that the water supply may contain disease-causing organisms resulting from fecal contamination.   Contact Environmental Health if you have questions regarding your water sample results.

Nitrate, Partial Chemical and Arsenic Analysis

Table 1 lists four parameters where federal and state agencies have established drinking water health advisory levels for public water supplies. Parameters listed in Table 2 are associated with aesthetic water quality problems.

Test results are reported in milligrams per liter (mg/L), equivalent to parts per million.
¹USEPA drinking water standard is 10 mg/L for nitrates and 1 mg/L for nitrite.
²Optimal range of fluoride concentration per American Dental Association
³USEPA drinking water standard is 4 mg/L

Unless your water well is properly designed, constructed, and maintained, a test result conforming to state standards may give you a false sense of security. A poorly constructed well can produce intermittent satisfactory bacteriological results, therefore continued safety of the water supply cannot be assured.