Defining “Blue Water” – the standards behind global water quality

Water/wastewater

Defining “Blue Water” – the standards behind global water quality

18 Feb, 2026
ASTM International
5 min read
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From microplastics to regulatory compliance, the concept of “Blue Water” is reshaping how environmental professionals approach the monitoring and analysis of our most critical resource.

In the lexicon of environmental monitoring, water is rarely just “water.”

It is a matrix of variables – defined by its source, usage and its constituents.

Whether it is ultrapure process water, treated effluent or ambient groundwater, the accuracy of its analysis relies on a foundational bedrock of consensus standards.

This invisible infrastructure is the domain of ASTM International Committee D19 on Water.

Established in 1932, the committee has evolved alongside the science of hydrology and analytical chemistry.

Today, its work encompasses a concept coined by the organisation as “Blue Water” standards – a shorthand term representing the vast array of water-related standards that directly impact society.

This umbrella covers everything from the drinking water in our pipes to sewage treatment, stormwater runoff and the detection of ubiquitous emerging contaminants like microplastics.

For laboratory managers and environmental engineers responsible for compliance, understanding these standards is not just a matter of protocol; 

it is the key to ensuring data validity in an increasingly regulated world.

 

The scope of “Blue Water”

The mandate of Committee D19 is vast, reflecting the complexity of the global water cycle.

According to William Lipps, the committee’s second vice chair, the scope extends far beyond simple purity checks.

“Just about all of the standards developed and maintained by the committee pertain to water quality,” says Lipps.

“Many of our standards are for the chemical, radiological and biological testing of water for contaminants and water quality.

“However, we also have standards that cover sampling and purification of water.”

This comprehensive approach ensures that the “Blue Water” concept applies equally to diverse matrices.

“These standards cover drinking water, wastewater, cooling and industrial waters, ambient water (rivers and lakes), stormwater runoff, seawater and brines,” Lipps adds.

For environmental professionals, this breadth is critical.

A standard that works for a pristine reservoir sample may fail when applied to complex industrial brine.

By maintaining distinct yet harmonised standards for various matrices, D19 ensures that analytical results remain comparable and legally defensible.

 

Speaking the same language

Before a sample can be analysed, the industry must agree on what is actually being measured.

This is where the work of the Subcommittee on Terminology (D19.12) becomes essential.

In a global industry, ambiguity is a risk; if two laboratories define “surface water” differently, their data cannot be meaningfully compared.

“How do you define groundwater and surface water? 

How do you decide on units of measurement? In our committee, the subcommittee on terminology is responsible for standardising terminology related to water,” explains Jay Gandhi, chair of the D19.12 subcommittee.

The result of this work is ASTM D1129, the Standard Terminology Relating to Water.

“This document provides definitions used by all the D19 subcommittees in their standards-development work,” Gandhi notes.

For example, it provides the codified definition of “surface water,” ensuring that when a regulator in Europe reads a report from a consultant in North America, they are speaking the exact same technical language.

 

The microplastics challenge

Perhaps no topic better illustrates the need for “Blue Water” standards than the rise of microplastics.

Fragments of material less than 5mm in size – created as plastic bottles degrade or synthetic fleece is washed – are now found virtually everywhere on Earth, including inside the human body.

For environmental labs, microplastics present a unique analytical challenge.

Unlike dissolved metals or organic compounds, microplastics are physical particles that vary wildly in shape, polymer type and size.

“Different people have different concepts or theories regarding microplastics, but the good news is that we are aware of the issue and that efforts are underway to create standardised methods,” says Gandhi.

Without a standardised method, one lab might count a particle that another lab ignores, rendering the data useless for regulatory decision-making.

Here, ASTM D19 has taken a leading role.

“D19 has led the world in publishing methods for the sampling, sample preparation and analysis of microplastics in water,” states Lipps.

A key output of this effort is ASTM D8402, the Standard Practice for Development of Microplastic Reference Samples for Calibration and Proficiency Evaluation.

This standard allows laboratories to calibrate their instruments against known reference samples, ensuring that their detection of microplastics in water matrices – whether high or low in suspended solids – is accurate and reproducible.

 

Bridging science and regulation

The value of these standards extends beyond the laboratory bench; they act as a bridge to regulatory compliance.

In the United States, the relationship between voluntary consensus standards and federal regulation is codified.

“The water committee has a subcommittee that liaises with other voluntary consensus-based organisations, like Standard Methods, the International Organization for Standardization (ISO), and the US Environmental Protection Agency (EPA),” Lipps explains.

This collaboration has practical implications for IET readers.

“Many D19 methods have been adopted by the EPA under the National Technology Transfer and Advancement Act of 1995, which allows customers of water utilities to use ASTM test methods as part of their regulatory toolbox.”

This means that for many environmental professionals, following an ASTM standard is not just best practice – it is a pathway to regulatory approval.

 

A resilient future

The “Blue Water” initiative is not static.

As climate change alters precipitation patterns and urbanisation changes runoff dynamics, the standards must evolve.

The committee is actively working on standards related to stormwater management, ensuring that designs for water flow mimic natural landscapes.

Furthermore, work is being conducted by the subcommittee on determining the effects of biogenic sulphuric acid on concrete pipes (C13.03), addressing the physical resiliency of sanitary sewage infrastructure.

Ultimately, “Blue Water” is about more than just the liquid itself; it is about the framework of trust that allows us to manage it.

By defining terms, refining analytical methods and aligning with regulators, the standards developed by Committee D19 ensure that when we test, monitor, or treat water, we are doing so with scientific certainty.

Adapted from the article Water, Water, Everywhere: Standards for Blue Water orginally published by ASTM International, with permission from Standardization News (Vol. 53, No. 3, May/June 2025, pp 24-29).

Lab Asia 33.2 April

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