Bacteriological Potable Water Sampling Instructions

Use this page to request bacteriological sampling of your private water well:

Below you will find the instructions on how to collect a water sample for submission to the State Lab for a total coliform bacteria presence / absence test. Accurate testing of any sample in the laboratory begins with proper sample collection. In the case of bacteriological testing, this means thorough disinfection of the sample collection point prior to sampling.

Office of Public Health Central Laboratory
FEE: $40.00
Please make checks payable to: LDH/OPH/LAB

Private water samples are accepted by the laboratory Monday through Thursday of each week (excluding holidays) by 2:00 PM at any of the following addresses:

LDH-OPH Central Laboratory
1209 Leesville Avenue
Baton Rouge, LA 70803
(225) 219-5207

The driveway to the left of the building (as you stand facing the building) will take you to the receiving area in the back of the building, where samples are dropped off by submitters and received by the laboratory personnel.

LDH-OPH Amite Regional Laboratory
104 North 1st Street, Suite A
Amite, LA 70422
(985) 748-2011

LDH-OPH Shreveport Water Laboratory
1035 Creswell Avenue
Room 352
Shreveport, LA 71101

If you have any questions, you may reach us by calling the laboratory at any of the above phone numbers.

Private water samples collected by a person other than regulatory personnel (an individual working for or approved by the State of Louisiana Water Regulatory) are considered unofficial and cannot be used for legal purposes.

**It is recommended that the sample be collected from a faucet as close to the well as possible.

**It is not recommended that the sample be collected from either a kitchen or bathroom faucet.

Samples are tested each Mon.-Thurs. at 2:00 PM. Samples cannot be over 30 hours old from the time of collection at the time of testing.

Procedure for Collecting Potable Water Bacteriological Samples


  1. Select the tap (faucet) from which the sample will be collected.
    • The selected tap should be a cold water tap.
    • The selected tap should allow sampling without touching the inside of the collection bottle.
    • The selected tap should not have a leaky valve stem, screw-on vacuum breaker, or a swivel faucet.
    • DO NOT flame the tap with a propane torch and DO NOT use any other cleaning agent such as alcohol on the tap either prior to or after flushing of the selected tap (flaming destroys the rubber gaskets in the faucet).
  2. Allow water to run until there is a noticeable temperature change in the water, usually 2 to 3 minutes.
  3. While the water continues to run, use a permanent marker to write the S# from the bottom of the Lab 8 form onto the bottle, just above the 100 mL line, but below the shoulder of the bottle. The form should be filled as follows:
    • 1 of 1
    • Project code: 200
    • Name and phone number of water supply
    • Address of water supply
    • Parish of water supply
    • Name of individual collecting the sample (“collected by”)
    • Place a line through the blank for Public Water Supply
    • Record the Date Collected
    • Record the Time the sample was collected in 24:00 hour format (Ex., if the sample was collected at 1:00 PM, the 24 hour format would be 13:00)
    • Record the Point of Collection
  4. With clean hands, remove the plastic wrap from the bottle and carefully fill the bottle to the 100 mL fill line. Replace the cap onto the bottle. Remove the S# strip located on the bottom of the Lab 8 form using the perforations and affix only the numbered portion to the top of the cap, discarding the remaining, unnumbered, strip.

Use this page to request bacteriological sampling of your private water well: