Bacteriological Sampling Requirements

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Who is Required to Sample and When?

Positive Results! What Should I Do?

Assistance

All public water systems in the State of Florida are required to conduct bacteriological sampling in accordance with Chapter 62-550.518 of the Florida Administrative Code.

Bacteriological sampling is conducted under an EPA rule known as the Total Coliform Rule (TCR).

Although the federal Ground Water Rule (GWR) has not been incorporated into the Florida Administrative Code (F.A.C.), Florida's public water systems (PWSs) that use ground water will have to comply with the GWR beginning December 1, 2009.
Bacteriological samples are analyzed for the presence of total coliform bacteria. The presence of these bacteria is an indicator that other forms of bacteria may be present.
If a laboratory detects total coliform bacteria, it will further analyze the sample for E. coli

Who is required to sample and when?

All transient non-community water systems are required to take one raw well water sample (from each well in service) and two samples from the distribution system each calendar quarter.
All non-transient non-community and community water systems are required to take a minimum of one raw well water sample (from each well in service) and a minimum of two samples* from the distribution system each month.
* There is a sliding scale for the required numbers of bacteriological distribution system samples that are required based on a system's population Rule 62-550-518.(2), Florida Administrative Code.

My results came back positive! What should I do?

For all unsatisfactory bacteriological sampling, send the results to the Department immediately. Do not wait until the 10th of the following month.
For a total coliform positive well sample:
- Take one repeat well sample.
- If the repeat sample is also total coliform positive, you will be required to
  - inspect the well,
  - correct any deficiencies,
  - disinfect the well per AWWA Standards, and
  - collect repeat samples.
- If the second repeat well sample is also total coliform positive, please contact the Department for further guidance.
For an E. coli positive well sample:
- The system must take the following actions within 24 hours of lab notification:
  - Notify the Department of the E. coli positive well sample.
  - Provide a DEP approved Tier 1 GWR Public Notice.
    - Precautionary boil water notice language is required to be in the notice unless conditions are met and approval is given by the Department to omit this language.
  - Take five back to back samples from the well.
    - If any of these well samples are E. coli positive, a second DEP approved Tier 1 GWR Public Notice will need to be issued within 24 hours of laboratory notification. Please contact the Department for corrective action guidance and approval of the Public Notice.
- Note: If the Tier 1 Public Notice includes boil water language, and any of the five back to back well samples are E. coli positive, two consecutive days of distribution samples absent for coliform will also need to be collected in order to rescind the Boil Water Notice.
For a total coliform positive distribution system sample:
- For systems that sample monthly:
  - At least three repeat samples are required to be taken. One from the original sample location, one each from within 5 service connections upstream and downstream of the original location.
  - One source water (well) sample for each day one or more TC+* routine distribution system sample(s) were collected by a GWS from each well pumped on the day the TC+ sample(s) was (were) collected must be collected within 24 hours of laboratory notification unless the source water sample(s) were collected on the same day. (This sampling is also known as triggered source water sampling.)
  - In the month after a total coliform positive distribution system sample, a total of at least 5 distribution system samples must be collected.
  - If positive samples continue, the water system shall repeat the above process until samples come back negative or until the maximum contaminant level (MCL) is exceeded. If the MCL is exceeded, contact the Department for further guidance and approval of the required Public Notice.
  - An E. coli positive repeat distribution system sample that follows a total coliform routine compliance sample is a violation that poses an Acute risk to health and public notification is required within 24 hours. Please call the Department immediately for further guidance.
- For systems that sample quarterly:
  - At least four repeat samples are required to be taken.
  - One source water (well) sample for each day one or more TC+* routine distribution system samples were collected by a GWS from each well pumped on the day the TC+ sample(s) was (were) collected must be collected within 24 hours of laboratory notification unless the source water sample(s) were collected on the same day. (This sampling is also known as triggered source water sampling.)
  - In the month after a total coliform positive distribution system sample, a total of at least 5 distribution system samples must be collected, even if the following month is still within the same quarter.
  - If positive samples continue, the water system shall repeat the above process until samples come back negative or until the maximum contaminant level (MCL) is exceeded. If the MCL is exceeded, contact the Department for further guidance and approval of the required Public Notice.
  - An E. coli positive repeat distribution system sample that follows a total coliform routine compliance sample is a violation that poses an Acute risk to health and public notification is required within 24 hours. Please call the Department immediately for further guidance.
- *Exceptions to the triggered source water monitoring requirements: a TC+ routine distribution sample is considered directly related to distribution system conditions, and the GWS is not required to conduct triggered source water monitoring under §141.402(a), if all the following Department criteria are met:
- The TC+ routine distribution system sample is FI-negative;
- The GWS has no uncorrected significant deficiency at its well(s);
- The GWS has no uncorrected assessment source water monitoring violation; and
All the GWS's well samples are FI-negative dating back to, and including, all those well samples taken during the most recent month or quarter when the GWS took all its required assessment raw water samples.

For an E.coli positive routine compliance distribution system sample:
- Repeat samples shall be taken in accordance with the steps listed above for a total coliform positive distribution system sample.
  - A total coliform positive repeat distribution sample that follows an E. coli positive routine compliance sample is a violation that poses an Acute risk to health and public notification is required within 24 hours. Please call the Department immediately for further guidance.
- In the month after an E. coli positive distribution system sample, a total of at least 5 distribution system samples must be collected.
Consecutive Systems:
- Consecutive systems must notify the wholesale Ground Water System of any total coliform or E. coli positive routine distribution samples within 24 hours of laboratory notification. The wholesale system will need to collect the triggered source water samples within 24 hours of being notified by the consecutive system. If any of the triggered source water samples are Fecal Indicator positive, the wholesale system must notify all consecutive systems it gives water to within 24 hours.

For Additional Assistance:

In House Compliance Contacts
EPA document explaining Bacteriological sampling, also known as the Total Coliform Rule monitoring. [.pdf 114kb]
EPA document explaining the Ground Water Rule. [.pdf 14,718 kb]
State of Florida document explaining the Ground Water Rule [.pdf 897 kb]
Visit the American Water Works Association (AWWA) website to obtain the current AWWA Standards listed below:
- AWWA Standards for Disinfection of Water Treatment Plants
- AWWA Standards for Disinfection of Water Mains
- AWWA Standards for Disinfection of Water Storage Facilities