Why do I need to test my water supply for bacteria?
Test your private water supply for two types of bacteria (total coliform, E. coli) to make sure it is safe to drink.
Samples that are collected for real estate, commercial, and agricultural reasons won’t be tested by Environmental Public Health.
Municipal (town or city) water sources are tested regularly for safety by each municipality. The most recent water results for your town or city is reported on this
website.
Contact your municipal office for any other drinking water test results. Please don’t submit your own sample of municipal water for testing.
Read all the information in this handout
before you collect a sample. You will need to follow the instructions below to get a good sample that is not contaminated.
How often do I need to test my water for bacteria?
It is a good idea to test your water for bacteria twice a year to make sure it is still safe to drink.
What do I need to know about water testing?
Samples are only accepted if they are:
- collected in an approved sampling bottle
- from a water supply that people eat or drink from
- with a completed requisition form
Samples are
not accepted for real estate transactions, research, agricultural or other commercial purposes.
Samples must be collected from the cold water supply line.
Do not:
- rinse the sampling bottle
- let water overflow or splash down the side of the bottle
- put the cap on a countertop (it can get contaminated)
- open the bottle until you are ready to collect your sample
- touch the inside of the cap, mouth, or neck of the bottle
- collect samples from a garden hose, outside tap, or other place that might be dirty
You can find information about where and when you can drop off your sample by calling
Environmental Public Health.
How do I collect a water sample?
- Wash your hands with soap and warm water.
- Take the sample from a cold water tap. Use a tap without a screen or remove the screen before you collect the sample.
- Let the cold water run constantly for at least 2 minutes before you collect the sample.
- Hold the bottle near the base of the tap to get the sample. Fill it past the 200 mL mark (to the shoulder of the bottle).
Do not overfill the bottle.
- Put the cap on the bottle
right away. Make sure the cap is secure, but do not overtighten it.
- Put the identification label from the requisition form on the bottle.
- Fill out the requisition and include the information below. If you miss anything on the requisition, your sample might not be processed.
- name and daytime phone number
- mailing address and postal code
- collection site (e.g., kitchen sink)
- legal land description and/or civic address
- date and time sample was collected
- name of person who collected the sample
On the requisition form, write down if this is a re-sample. You also need to fill out section A (Drinking Water) and add any comments or special requests at the bottom of the requisition. - Put the sample and requisition form in the plastic bag that came with the sample bottle.
- Put the sample in a cooler filled with ice packs and bring it to a drop-off location near you
right away.
The sample needs to be as fresh as possible. It takes time to get the sample from the drop off location to the lab. Collect the sample just before you leave for the drop off location. This is important because if the sample arrives at the lab more than 24 hours after it’s collected, it will
not be processed. Check
here to see where and when you can drop off the sample in the town or city nearest you. |
How do I find out the results?
All results are mailed to the address you gave on the requisition form. If your results show bacteria, a Public Health Inspector will try to call you. Make sure your daytime phone number on the requisition is the best one to reach you at.
If you think your drinking water is unsafe or you have any questions, call
Environmental Public Health.
