Total Coliform Rule (TCR)

General The purpose of the TCR is to protect the water system from microbial contamination TCR requires the water system to monitor for total and fecal coliform bacteria. TCR applies to all community and non-community water systems

What is a coliform? A group of bacteria that include both pathogenic and non-pathogen species Gram negative, spore-forming rod shaped bacteria that ferments lactose at 35oC Indicator organism Always present in fecal contamination More persistent in water than pathogenic bacteria

Definitions Bacteria Coliform Bacteria Pathogenic Bacteria Fecal Coliform / E. coli Pathogenic Bacteria Routine Sample Repeat Sample Replacement Sample Other Sample

TCR Test Methods Test volume is at least 100 mL Test results are reported as either “Present” or “Absent” per 100 mL sample Bacterial enumeration (counting) is not required

TCR Approved Test Methods

Who can take TCR samples? Certified water treatment / distribution operators Persons trained to collect samples by DHS / LPA A certified laboratory technician

TCR Requirements: Develop a sample siting plan (update at least every 10 years) Collect routine, repeat and replacement samples as required by TCR for your water system Notify DHS or your LPA (County Health Department) when there is an increase in coliform bacteria Comply with the total coliform MCL

Other Coliform Sampling: In addition to following your sample siting plan, take additional bacteriological analyses when: After construction or repair of wells (following disinfection, but before return to service After main installation or repair After construction or repair of storage facilities Whenever system pressure drops below 5 psi These special samples are not used to compute MCL compliance

TCR Sample Siting Plan Location of routine samples Chose sites that are representative of the distribution system including: All pressure zones Each water source Each distribution reservoir Sites should be rotated if representative sites exceeds the number of samples taken each month.

Sample Siting Plans It is strongly recommended that locations repeat sample sites be included in the sample siting plan

Tips for Selecting the Best Sample Sites Accessible Above “big dog” height or otherwise protected Consider dedicated sample taps No leaking valves or packings Good flow control No bushes or vegetation Can be flamed or cleaned Can be flushed vigorously without causing problems with the homeowner

Repeat Sample Site Selection 1st Repeat site is the original location Site 2 & 3 must be within 5 service connections upstream and 5 service connections downstream (further from source) Chose repeat sites using the same criteria as routine sites System taking less than 5 routine samples per month must take a 4th repeat sample at a location acceptable to DHS/LPA

Routine Sampling Number of routine samples/month determined by system size Minimum frequency of sampling is one per month for small systems (25 to 1000 population Samples shall be collected at regular intervals throughout the month

Repeat Samples When any routine, repeat or replacement sample is total coliform positive the water system shall: Collect a repeat sample set within 24 hours of being informed of the positive sample Repeat sample set is required for each positive routine, repeat or replacement sample

Repeat Sample Set Three samples (small systems take 4 repeat samples) One sample from the original total coliform sample location Other repeat samples shall be taken within five service connections upstream or downstream of original location.

Significant Rise in Bacterial Count Significant rise in bacterial count occurs when : System has a positive for fecal or E.coli System fails the total coliform MCL

Significant Rise in Bacterial Count When a system has a significant rise in bacterial count it must: Contact DHS/LPA by the end of the day (no later than 24 hours) Submit a review of water system conditions that could contribute or cause the problem Implement emergency notification plan as directed by DHS/LPA

Total Coliform MCL All routine, repeat and replacement samples taken in a calendar month are used to calculate MCL compliance Special samples (after maintenance samples) are not used to determine MCL compliance Special samples must be properly labled

Acute Coliform MCL An Acute MCL violation occurs when: Any repeat sample is fecal coliform / E.coli positive, or Any repeat sample following a routine fecal positive is total coliform positive

Total Coliform MCL Systems in violation of the Total Coliform MCL shall: Notify DHS/LPA within 24 hours Notify consumers of water system