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Chemical Sampling for Public Water Systems

Information about sampling and monitoring requirements for public water systems

Every public water system (PWS) in Texas must sample for chemical contaminants. Sampling for chemical contaminants differs from lead and copper, water quality parameters, microbiological, and disinfectant residual sampling because TCEQ uses contractors to collect these samples. Samples collected by contractors include asbestos, arsenic, disinfection byproducts, minerals, metals, nitrate, nitrite, radionuclides, Synthetic Organic Compounds (SOCs), and Volatile Organic Compounds (VOCs). The contractors use the information in Drinking Water Watch to contact the PWS to schedule an appointment, so you must ensure this information is up to date. If contact or facility information needs to be updated, email the Drinking Water Inventory & Protection Team at Instructions for Texas Drinking Water Watch tell you where to find contact information, sample schedules, violations, and sample results for public water systems.

How are Chemical Monitoring Schedules Determined?

The number of samples and monitoring frequency is determined by:

  • Public water system type
    • Community (C)
    • Nontransient, noncommunity (NTNC)
    • Transient, noncommunity (TNC)
  • Population of the water system based on the most recent regional investigation
  • Source water type
    • Surface water
    • Ground water
    • Purchased water
  • Source water assessments for regulated chemicals
  • Previous sample results - increases or the detection of new contaminants
  • New rules can change sampling requirements for water systems
  • When facilities are activated or deactivated

The rules for chemical sampling requirements can be found in  Standards and Reporting Requirements for Public Water Systems.

If you would like to calculate your estimated cost for chemical analysis, see Calculating Your Annual Cost of Chemical Compliance Sampling. at any time during the year. If you have questions about your sample schedule contact the Drinking Water Quality Team at or (512) 239-4691.

Where are Chemical Samples analyzed?

Chemical samples are analyzed by laboratories at the Department of State Health Services    or Lower Colorado River Authority  . Asbestos samples are analyzed by laboratories specified by the Public Water System Supervision Program (PWSSP).

Monitoring for Lead and Copper and Bacteriological Samples

Visit Lead and CopperRevised Total Coliform Rule, and Groundwater Rule for sampling information.

Assistance and Helpful Links

TCEQ's Financial, Managerial, and Technical (FMT) Assistance program offers free financial, managerial, and technical assistance to help public water and wastewater systems comply with regulations.

Public Notice Language for Drinking Water Compliance

Public Water System Monitoring Plans