A&B Labs, An AmSpec Group Company
Safe drinking water is not assumed — it is verified.
For municipalities, utilities, industrial facilities, schools, healthcare systems, and commercial buildings, microbial monitoring is a regulatory requirement and a public health responsibility. At A&B Labs, An AmSpec Group Company, our Drinking Water Testing Package includes two foundational microbiological analyses:
- Total Coliform & E. coli
- Heterotrophic Plate Count (HPC)
Together, these tests provide critical insight into system integrity, treatment effectiveness, and distribution system health.
Why Coliform Testing Matters
What Are Total Coliforms?
Total coliform bacteria are a group of microorganisms commonly found in soil, vegetation, and surface water. While most are not harmful themselves, their presence in drinking water can indicate:
- Pathogen intrusion
- Treatment failure
- Distribution system breaches
- Post-treatment contamination
Under the U.S. Environmental Protection Agency (EPA) Revised Total Coliform Rule (RTCR), public water systems are required to routinely monitor for total coliform bacteria.
If total coliform is detected, the sample must be further analyzed for E. coli, a specific indicator of fecal contamination and potential health risk.
Regulatory Context
The EPA sets the Maximum Contaminant Level (MCL) for E. coli at zero in drinking water systems.
Detection triggers:
- Repeat sampling requirements
- System assessments
- Corrective action
- Public notification (in certain cases)
For systems regulated under the Safe Drinking Water Act (SDWA) and state agencies such as TCEQ in Texas, defensible microbiological data is not optional — it is required.
What Is Heterotrophic Plate Count (HPC)?
HPC measures the concentration of general heterotrophic bacteria present in water.
Unlike coliform testing, HPC does not target specific pathogens and microbes. Instead, it evaluates overall microbial load within the distribution system.
Why HPC Is Important
Elevated HPC levels may indicate:
- Biofilm formation within pipes
- Stagnation or low disinfectant residual
- Infrastructure aging
- Changes in water chemistry
HPC is particularly valuable for:
- Routine distribution system monitoring
- Post-maintenance verification
- Private water systems
- Industrial and healthcare facilities
- Bottled water quality control
While there is no federal MCL for HPC, it is widely used as an operational control parameter to assess system stability and sanitation effectiveness.
How Coliform & HPC Work Together
Coliform testing answers:
Is there evidence of contamination or pathway failure?
HPC testing answers:
What is the overall microbial condition of the system?
When performed together, these analyses provide a more complete picture of drinking water safety and infrastructure performance.
Who Needs This Testing Package?
Our Coliform & HPC package supports:
- Municipal public water systems
- Non-transient non-community systems
- Schools and universities
- Healthcare facilities
- Industrial plants
- Commercial buildings
- Real estate transactions
- Private well owners
Whether required for regulatory compliance or proactive system monitoring, reliable laboratory data is essential.
Defensible Data Matters
At A&B Labs, our microbiology team operates under rigorous quality standards to ensure:
- Proper sample handling and preservation
- Method compliance
- Accurate incubation protocols
- Clear reporting
- Regulatory-ready documentation
In drinking water testing, speed and accuracy are equally critical.
A Proactive Approach to Water Safety
Microbiological monitoring is not simply about passing a test — it is about protecting communities, safeguarding infrastructure, and maintaining regulatory confidence.
If you are responsible for a water system — public or private — routine microbial monitoring is one of the most important safeguards you can implement.
Contact A&B Labs today to learn more about our Drinking Water Testing Package.
📧 marketing@amspecgroup.com