Bacteriological Sample Collection

Beginning January 1, 2017, the Safe Drinking Water Program will reinstate the bacteriological sample collection program for all public water systems statewide.  Additionally, the Safe Drinking Water Program will begin to collect and analyze the total trihalomethanes (TTHMs) and haloacetic acids (HAA5) samples for water systems statewide. The Department will continue to provide sample collection containers and forms, scheduled transportation of routine samples from our parish health units to our state laboratories, and analysis of these samples.  Bacteriological samples submitted to the LDH Laboratories must be collected in a sample container supplied by LDH.  Bacteriological samples collected in a non-LDH sample container will be rejected.

Regional Office Map   

State Laboratory Directory

Chart - RTCR Required number of samples, sites and disinfectant residuals

Bacteriological Sample Collection Bottles
NOTE: As of April 1, 2015, the LDH Laboratories have switched to IDEXX sample bottles for the collection of bacteriological samples. Whirl-Pak bags are no longer accepted by the LDH Laboratories.  IDEXX sample bottles can be picked up at the sample depots and LDH laboratories.  Please pick up only what you need, as the IDEXX bottles are for all water systems in the State.

Sample Collection tips and rejection criteria - Do not let the sodium thiosulfate fall out of the IDEXX bottle (powder)

- Fill the IDEXX bottles to the 100 mL line.  Overfilling and underfilling samples will result in sample rejection

- The LDH Laboratories no longer accept Whirl-Pak bags.  Sample received in Whirl-Pak bags will be rejected

- IDEXX Water Vessels Expirations




***REVISED Bacteriological Sample Monitoring and Collecting Presentations***

Bacteriological Monitoring Requirements - Revised Total Coliform Rule (TCR) and Ground Water Rule (GWR) requirements for bacteriological sampling.

Bacteriological Sample Collection Procedures - Procedure for collecting samples with new IDEXX sample bottles and preparation of samples for transport to the laboratory.

Approved Bacteriological Sample Taps - Requirements of what is an approved sample tap for sample collection.

Sample Tap Selection - Information on identifying suitable taps for bacteriological sample collection.  Also identifies taps to avoid.

Lab 8 Form - Instructions on completing the lab 8 form for submitting samples to the State Laboratory.

Hach Test Kit for Chlorine Residuals - Instructions on collecting a low/high range chlorine residual with the Pocket Colorimeter II. Always refer to the manual provided with the Pocket Colorimeter II.  This presentation is for additional clarification.

Helpful videos

Sample Pick-up Times and Locations

Bacteriological Sample Truck Routes

Below are truck routes for for the transport of Monthly Bacteriological samples to the State Laboratories (Baton Rouge, Shreveport, Amite).  Please plan accordingly to make scheduled pick-up times so samples can reach the lab within the 30-hr hold time.


North Sample Truck Routes - Effective 10/27/2020

South Sample Truck Route Effective 1/3/2023 

Laboratory Operation Schedule